Recovery of lithium from liquid streams using solute permeable membranes

Abstract

Methods and systems related to the recovery of lithium (e.g., lithium salts) from a liquid stream are provided. In some embodiments, the method involves obtaining lithium (e.g., as a solid lithium salt) by removing at least a portion of the liquid from the feed stream to form a concentrated stream with respect to dissolved lithium cations. Liquid removal may include delivering at least a portion of the feed stream to a membrane separator and / or a humidifier. Some methods include removing impurities (e.g., non-lithium cations) from the concentrated stream (e.g., via precipitation and / or crystallization). In some embodiments, a solution comprising dissolved lithium cations and anions is electrochemically treated such that a first dissolved anion is replaced by a second, different anion. In some embodiments, a solid lithium salt comprising at least a portion of lithium cations and second anions is obtained (e.g., precipitation and / or crystallization via concentration of an electrochemically treated solution in a humidifier).

Description

[0001] Related Applications

[0002] This application claims priority under 35 USC §119(e) to U.S. Provisional Patent Application No. 63 / 411,075, filed on September 28, 2022, entitled “Lithium Recovery from Liquid Streams Using Solute-Permeable Membranes,” which is incorporated herein by reference in its entirety for all purposes. Technical Field

[0003] Methods and systems are provided that relate to recovering lithium (eg, lithium salts) from liquids. Background Art

[0004] Lithium is a commercially valuable resource that can be recovered from a variety of sources such as brines (e.g., seawater, salt lake brines, groundwater), ores, and waste products such as lithium-ion batteries. Lithium is typically found as dissolved ions in liquid mixtures with other non-lithium species. Improved methods and systems for obtaining lithium, including relatively high purity lithium salts in some cases, are desired. Summary of the invention

[0005] Methods and systems are provided that relate to the recovery of lithium (e.g., lithium salts) from liquid streams. In some cases, the subject matter of the present invention relates to related products, alternative solutions to a particular problem, and / or a plurality of different uses of one or more systems and / or articles.

[0006] In one aspect, a method is provided. In some embodiments, the method includes removing at least a portion of the liquid from a feed stream comprising the liquid, dissolved lithium cations, and dissolved non-lithium cations to form a concentrated stream having a higher concentration of dissolved lithium cations than the feed stream, wherein the removing includes: (a) conveying a first membrane separator retentate inlet stream comprising at least a portion of the feed stream to a retentate side of the first membrane separator such that: a first membrane separator retentate outlet stream exits the retentate side of the first membrane separator, and the dissolved lithium cations in the first membrane separator retentate outlet stream are removed from the retentate side of the first membrane separator; The method comprises the steps of: (a) transferring a second membrane separator retentate inlet stream containing at least a portion of the first membrane separator retentate outlet stream to the retentate side of the second membrane separator, wherein the concentration of ions is greater than the concentration of dissolved lithium cations in the retentate inlet stream of the first membrane separator, and at least a portion of the liquid from the retentate inlet stream of the first membrane separator is transported from the retentate side of the first membrane separator through the semipermeable membrane of the first membrane separator to the permeate side of the first membrane separator; and (b) transporting a second membrane separator retentate inlet stream containing at least a portion of the first membrane separator retentate outlet stream to the retentate side of the second membrane separator, so that: the second membrane separator retentate outlet stream leaves the retentate side of the second membrane separator, and the second membrane separator passes through the semipermeable membrane of the first membrane separator. The concentration of dissolved lithium cations in the separator retentate outlet stream is greater than the concentration of dissolved lithium cations in the second membrane separator retentate inlet stream, and at least a portion of the liquid from the second membrane separator retentate inlet stream, at least a portion of the dissolved lithium cations, and at least a portion of the dissolved non-lithium cations are transported from the retentate side of the second membrane separator through the semipermeable membrane of the second membrane separator to the permeate side of the second membrane separator; and (c) a humidifier liquid inlet stream comprising at least a portion of the second membrane separator retentate outlet stream is transported to a humidifier, and at least a portion of the liquid of the humidifier liquid inlet stream is evaporated within the humidifier to produce a humidified gas stream and a humidifier liquid outlet stream having a higher concentration of dissolved lithium cations than the humidifier liquid inlet stream, so that at least a portion of the humidifier liquid outlet stream is part of a concentrate stream; and at least some of the dissolved non-lithium cations are removed from the concentrate stream to form a decontaminated concentrate stream having an atomic ratio of dissolved lithium cations to dissolved non-lithium cations greater than the atomic ratio of dissolved lithium cations to dissolved non-lithium cations in the concentrate stream.

[0007] In some embodiments, the method includes: removing at least a portion of the liquid from a feed stream comprising the liquid, dissolved lithium cations, and dissolved non-lithium cations to form a concentrated stream having a higher concentration of dissolved lithium cations than the feed stream, wherein the removing includes: (a) conveying a first membrane separator retentate inlet stream to a retentate side of the first membrane separator such that: a first membrane separator retentate outlet stream exits the retentate side of the first membrane separator, a concentration of dissolved lithium cations of the first membrane separator retentate outlet stream is greater than a concentration of dissolved lithium cations in the first membrane separator retentate inlet stream, and at least a portion of the liquid from the first membrane separator retentate inlet stream is passed from the retentate side of the first membrane separator through the first membrane separator; (a) transferring a second membrane separator retentate inlet stream comprising at least a portion of the first membrane separator retentate outlet stream to the retentate side of the second membrane separator, such that: the second membrane separator retentate outlet stream leaves the retentate side of the second membrane separator, the concentration of dissolved lithium cations in the second membrane separator retentate outlet stream is greater than the concentration of dissolved lithium cations in the second membrane separator retentate inlet stream, and at least a portion of the liquid from the second membrane separator retentate inlet stream, at least a portion of the dissolved lithium cations, and at least a portion of the dissolved non-lithium cations are transferred from the retentate side of the second membrane separator through the semipermeable membrane of the second membrane separator to the permeate side of the second membrane separator, wherein the permeate outlet stream of the second membrane separator leaves the retentate side of the second membrane separator, the concentration of dissolved lithium cations in the second membrane separator retentate outlet stream is greater than the concentration of dissolved lithium cations in the second membrane separator retentate inlet stream. (c) conveying a third membrane separator retentate inlet stream comprising at least a portion of the second membrane separator retentate outlet stream to the retentate side of the third membrane separator, such that: the third membrane separator retentate outlet stream leaves the retentate side of the third membrane separator, the concentration of dissolved lithium cations in the third membrane separator retentate outlet stream is greater than the concentration of dissolved lithium cations in the third membrane separator retentate inlet stream, and at least a portion of the liquid from the third membrane separator retentate inlet stream, at least a portion of the dissolved lithium, and at least a portion of the dissolved non-lithium cations are removed from the retentate side of the third membrane separator. The retentate side of the third membrane separator is transported to the permeate side of the third membrane separator through the semipermeable membrane of the third membrane separator, where a portion of the liquid, a portion of the dissolved lithium cations and a portion of the dissolved non-lithium cations form a portion or all of the third membrane separator permeate outlet stream that is transported out of the permeate side of the third membrane separator; and (d) transporting a humidifier liquid inlet stream comprising at least a portion of the third membrane separator retentate outlet stream to a humidifier, and causing at least a portion of the liquid of the humidifier liquid inlet stream to evaporate within the humidifier to produce a humidified gas stream and a humidifier liquid outlet stream having a higher concentration of dissolved lithium cations than the humidifier liquid inlet stream, so that at least a portion of the humidifier liquid outlet stream is part of the concentrate stream;and removing at least some of the dissolved non-lithium cations from the concentrate stream to form a decontaminated concentrate stream having an atomic ratio of dissolved lithium cations to dissolved non-lithium cations greater than the atomic ratio of dissolved lithium cations to dissolved non-lithium cations in the concentrate stream; wherein: the first membrane separator retentate inlet stream comprises at least a portion of the second membrane separator permeate outlet stream and / or at least a portion of the third membrane separator permeate outlet stream; and the second membrane separator retentate inlet stream and / or the third membrane separator retentate inlet stream comprises at least a portion of the feed stream. ;

[0008] In some embodiments, the method includes removing at least a portion of the liquid from a feed stream comprising the liquid and dissolved lithium cations to form a concentrated stream having a higher concentration of dissolved lithium cations than the feed stream, wherein the removing includes: conveying a first membrane separator retentate inlet stream comprising at least a portion of the feed stream to a retentate side of the first membrane separator such that: a first membrane separator retentate outlet stream exits the retentate side of the first membrane separator, the first membrane separator retentate outlet stream having a concentration of dissolved lithium cations greater than the concentration of dissolved lithium cations in the first membrane separator retentate inlet stream, and at least a portion of the liquid from the first membrane separator retentate inlet stream is conveyed from the retentate side of the first membrane separator through a semipermeable membrane of the first membrane separator to a permeate side of the first membrane separator; and conveying the first membrane separator retentate outlet stream comprising at least a portion of the feed stream to a retentate side of the first membrane separator. The second membrane separator retentate inlet flow of the flow is transported to the retentate side of the second membrane separator, so that: the second membrane separator retentate outlet flow leaves the retentate side of the second membrane separator, the concentration of dissolved lithium cations in the second membrane separator retentate outlet flow is higher than the concentration of dissolved lithium cations in the second membrane separator retentate inlet flow, so that at least a portion of the second membrane separator retentate outlet flow is a portion of the concentrated flow, and at least a portion of the liquid from the second membrane separator retentate inlet flow and at least a portion of the dissolved lithium cations are transported from the retentate side of the second membrane separator through the semipermeable membrane of the second membrane separator to the permeate side of the second membrane separator; wherein: the concentration of dissolved lithium cations in the feed flow is greater than or equal to 10 mg / L, and the ratio of the concentration of dissolved lithium cations in the concentrate flow to the concentration of dissolved lithium cations in the feed flow is greater than or equal to 4.

[0009] In some embodiments, the method includes: removing at least a portion of the liquid from a feed stream comprising the liquid and dissolved lithium cations to form a concentrated stream having a higher concentration of dissolved lithium cations than the feed stream, wherein the removing includes: conveying a first membrane separator retentate inlet stream to a retentate side of the first membrane separator such that: a first membrane separator retentate outlet stream exits the retentate side of the first membrane separator, the concentration of dissolved lithium cations of the first membrane separator retentate outlet stream is greater than the concentration of dissolved lithium cations in the first membrane separator retentate inlet stream, and at least a portion of the liquid from the first membrane separator retentate inlet stream is conveyed from the retentate side of the first membrane separator to the first membrane separator through a semipermeable membrane of the first membrane separator. a second membrane separator retentate inlet stream including at least a portion of the first membrane separator retentate outlet stream being transported to the retentate side of the second membrane separator, such that: the second membrane separator retentate outlet stream leaves the retentate side of the second membrane separator, the concentration of dissolved lithium cations of the second membrane separator retentate outlet stream is greater than the concentration of dissolved lithium cations of the second membrane separator retentate inlet stream, and at least a portion of the liquid and at least a portion of the dissolved lithium cations from the second membrane separator retentate inlet stream are transported from the retentate side of the second membrane separator through the semipermeable membrane of the second membrane separator to the permeate side of the second membrane separator, where a portion of the liquid and a portion of the dissolved lithium cations on the permeate side form a liquid transported out of the second membrane separator. and transferring a third membrane separator retentate inlet stream comprising at least a portion of the second membrane separator retentate outlet stream to the retentate side of the third membrane separator, such that: the third membrane separator retentate outlet stream leaves the retentate side of the third membrane separator, the concentration of dissolved lithium cations of the third membrane separator retentate outlet stream is greater than the concentration of dissolved lithium cations of the third membrane separator retentate inlet stream, such that at least a portion of the third membrane separator retentate outlet stream is part of the concentrate stream, and at least a portion of the liquid and at least a portion of the dissolved lithium cations from the third membrane separator retentate inlet stream pass from the retentate side of the third membrane separator to the third membrane separator. The semipermeable membrane is transported to the permeate side of the third membrane separator, where part of the liquid on the permeate side and part of the dissolved lithium cations form part or all of the third membrane separator permeate outlet flow that is transported out of the permeate side of the third membrane separator; wherein: the first membrane separator retentate inlet flow contains at least a part of the second membrane separator permeate outlet flow and / or at least a part of the third membrane separator permeate outlet flow; the second membrane separator retentate inlet flow and / or the third membrane separator retentate inlet flow contain at least a part of the feed flow; the concentration of dissolved lithium cations in the feed flow is greater than or equal to 10 mg / L, and the ratio of the concentration of dissolved lithium cations in the concentrate flow to the concentration of dissolved lithium cations in the feed flow is greater than or equal to 4.

[0010] Other advantages and novel features of the present invention will become apparent from the following detailed description of multiple non-limiting embodiments of the present invention when considered in conjunction with the accompanying drawings. In the event that this specification and the documents incorporated by reference include conflicting and / or inconsistent disclosures, this specification shall prevail. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying drawings, which are schematic and are not intended to be drawn to scale. In the drawings, each identical or nearly identical component shown is generally represented by a single reference numeral. For purposes of clarity, not every component is labeled in every drawing, nor is every component of every embodiment of the present invention shown, where illustration is not required for one of ordinary skill in the art to understand the present invention. In the drawings:

[0012] Figure 1A is a schematic diagram of a system for obtaining a lithium salt according to certain embodiments, the system comprising a membrane separator that receives a feed stream and produces a retentate outlet stream that can form part or all of a concentrate stream;

[0013] Figure 1B is a schematic diagram of a system for obtaining a lithium salt according to certain embodiments, the system comprising a membrane separator that receives a feed stream and produces a retentate outlet stream that may form part or all of a concentrate stream, and wherein a recycle stream is fed back to a retentate inlet stream of the membrane separator;

[0014] Figure 2A is a schematic diagram of a system for obtaining a lithium salt according to certain embodiments, the system including a humidifier that receives a feed stream and produces a humidifier outlet stream that can form part or all of a concentrate stream;

[0015] Figure 2B is a schematic diagram of a system for obtaining a lithium salt according to certain embodiments, the system including a humidifier that receives a feed stream and produces a humidifier outlet stream that can form part or all of a concentrated stream, and wherein the humidified gas stream from the humidifier can be fed to a dehumidifier for condensation;

[0016] Figure 3A is a schematic diagram of a system for obtaining a lithium salt according to certain embodiments, the system comprising a membrane separator and a humidifier;

[0017] Figure 3B is a schematic diagram of a system for obtaining a lithium salt according to certain embodiments, the system comprising a first membrane separator, a second membrane separator, and a humidifier;

[0018] Figure 3Cis a schematic diagram of a system including a first membrane separator and a second membrane separator according to some embodiments;

[0019] Figures 3D to 3G is a schematic diagram of a system for obtaining a lithium salt according to some embodiments, the system comprising a first membrane separator, a second membrane separator, and a third membrane separator;

[0020] Figures 3H to 3J is a schematic diagram of a system for obtaining a lithium salt according to some embodiments, the system comprising a first membrane separator, a second membrane separator, and an upstream membrane separator;

[0021] Figure 3K is a schematic diagram of a system for obtaining a lithium salt according to some embodiments, the system comprising a first membrane separator, a second membrane separator, a third membrane separator, and an upstream membrane separator;

[0022] Figure 4A is a schematic diagram of a system for obtaining a lithium salt according to certain embodiments, the system comprising a non-lithium-containing salt production unit that receives a concentrate stream and produces a concentrate stream depleted of impurities;

[0023] Figure 4B is a schematic diagram of a system for obtaining a lithium salt according to certain embodiments, the system comprising a non-lithium-containing salt production unit having a precipitation unit and a cooling unit;

[0024] Figures 5A to 5B is a schematic diagram showing an electrochemical cell in the case of an initial solution according to certain embodiments ( Figure 5A ) and during voltage application ( Figure 5B ) is a schematic diagram of an electrochemical cell;

[0025] Figure 5C is a schematic diagram of a system for obtaining a lithium salt according to certain embodiments, the system comprising an electrochemical cell and a humidifier;

[0026] Fig. 6A is a schematic diagram of a system for obtaining a lithium salt according to certain embodiments, the system comprising a membrane separator, a first humidifier, a non-lithium-containing salt generating unit, an electrochemical cell, a second humidifier, and a solid lithium salt forming unit;

[0027] Figure 6B is a schematic diagram of a system for obtaining a lithium salt according to certain embodiments, the system comprising a first membrane separator, a second membrane separator, a first humidifier, a non-lithium-containing salt generating unit, an electrochemical cell, a second humidifier, and a solid lithium salt forming unit;

[0028] Fig. 7A is a schematic diagram of a membrane separator of a single membrane according to certain embodiments;

[0029] Figure 7B is a schematic diagram of a membrane separator comprising a plurality of semipermeable membranes fluidly connected in parallel according to certain embodiments;

[0030] Figure 7C is a schematic diagram of a membrane separator including a plurality of semipermeable membranes fluidly connected in series according to certain embodiments;

[0031] Fig. 8A is a graph of percent recovery versus feed salinity for various membrane examples;

[0032] Figure 8B is a graph of percent rejection versus feed salinity for various membrane examples;

[0033] Fig. 9 is a schematic diagram of a system for obtaining lithium salts from brine according to certain embodiments;

[0034] Fig.10 is a schematic diagram of a system for obtaining a lithium salt from a solution containing anions such as sulfate and carbonate, according to certain embodiments;

[0035] Fig.11 is a schematic diagram of a system for obtaining a lithium salt from a solution obtained from a lithium-ion battery according to certain embodiments;

[0036] Fig.12 is a schematic diagram of a system for concentrating a lithium-containing stream according to certain embodiments;

[0037] Fig.13A is a schematic diagram of a system for obtaining a lithium salt according to certain embodiments, the system including a membrane separator that receives a feed stream treated by a boron selective media and produces a retentate outlet stream that can form part or all of a concentrate stream; and

[0038] Fig. 13B is a schematic diagram of a system for obtaining a lithium salt, according to certain embodiments, the system including a membrane separator that receives a feed stream and produces a retentate outlet stream that can form part or all of a treated concentrate stream that can be treated by a boron selective media.

[0039] Fig.14A is a schematic diagram of a system for obtaining a lithium salt according to some embodiments, the system comprising a first membrane separator and a second membrane separator;

[0040] Figures 14B to 14D is a schematic diagram of a system for obtaining a lithium salt according to some embodiments, the system comprising a first membrane separator, a second membrane separator, and a third membrane separator; and

[0041] Figures 15A to 15Cis a schematic diagram of a system for obtaining a lithium salt according to some embodiments, the system including a first membrane separator, a second membrane separator, and a third membrane separator. DETAILED DESCRIPTION

[0042] Provided are methods and systems for recovering lithium (e.g., lithium salts) from a liquid stream. In some embodiments, the method involves obtaining lithium (e.g., as a solid lithium salt) by removing at least a portion of the liquid from a feed stream to form a concentrated stream about dissolved lithium cations. Liquid removal may include conveying at least a portion of the feed stream to a membrane separator and / or a humidifier. Some methods include removing impurities (e.g., non-lithium cations) from the concentrated stream (e.g., via precipitation and / or crystallization). In some embodiments, a solution comprising dissolved lithium cations and anions is electrochemically treated so that a first dissolved anion is replaced by a second different anion. In some embodiments, a solid lithium salt comprising at least a portion of lithium cations and a second anion is obtained (e.g., via precipitation and / or crystallization after concentrating the electrochemically treated solution in a humidifier).

[0043] Recovering lithium (e.g., lithium salts) from liquids (e.g., brine, ore, battery waste) is a commercially and industrially important process. However, such recovery may be difficult because typical lithium sources also contain one or more impurities. For example, typical brines with considerable lithium ion content have concentrations of sodium, potassium, calcium that are several orders of magnitude higher, and in some cases, other ions such as magnesium, iron, aluminum, manganese, strontium and / or barium that are several orders of magnitude higher. Some strategies for separating lithium ions from potential impurities rely on chemical treatment of the liquid source. Chemical treatment can be used to selectively precipitate non-lithium cations. For example, a liquid source containing lithium, potassium and sodium can be chemically treated to form sulfates (e.g., by salt replacement reactions). Potassium sulfate and sodium sulfate, which have lower solubility than lithium sulfate, can be used for separation (e.g., via selective precipitation and / or concentration). These typical lithium separation technologies often require energy-intensive and / or slow concentrations (e.g., via solar concentration) and chemical treatment / separation processes, which are expensive and capital intensive.

[0044] In the context of the present disclosure, it has been recognized that improved liquid concentration techniques (e.g., in terms of energy consumption and / or speed) are possible by using liquid concentration and / or ion exchange techniques that are different from those commonly used for lithium recovery. For example, membrane-based separation and humidification / dehumidification techniques (used alone or in combination) can provide relatively high concentrations of lithium ions from various sources at a faster rate and / or lower energy consumption than typical techniques. In addition, membrane-based separation and humidification / dehumidification processes can promote greater liquid recovery rates, lower liquid consumption, and less waste generation that needs to be discharged compared to typical lithium recovery techniques. It is also recognized that electrochemical treatment of lithium-rich solutions can reliably and efficiently exchange anions in some cases to produce lithium salts with commercial value, such as lithium hydroxide. In some embodiments, electrochemical treatment techniques (e.g., electrolysis) can be easily integrated with membrane-based separation and / or humidification / dehumidification techniques to produce lithium in a desired form (e.g., solid lithium salts such as crystalline lithium hydroxide).

[0045] In some membrane-based separation processes (e.g., reverse osmosis and nanofiltration), hydraulic pressure is applied to promote liquid to pass through a semipermeable membrane. In many such systems, the amount of hydraulic pressure required to cause liquid to pass through the membrane is proportional to the difference in solute concentration and / or osmotic pressure between the retentate side and the permeate side of the membrane. It is desirable to configure a system and method for reducing the hydraulic pressure required for a given solute concentration and / or osmotic pressure in order to promote energy efficiency, increase the concentration limit and / or promote the durability of the system. It has been recognized that a method of reducing the required hydraulic pressure is to allow a larger portion of the inflow solute (e.g., containing dissolved lithium cations and / or dissolved non-lithium cations) to pass through the membrane compared to a reverse osmosis (RO) membrane with a high rejection rate (e.g., 99.9% rejection rate or 100% rejection rate). Such a membrane configuration can be used to process highly saline streams (e.g., desalination) because higher solute permeability can reduce the required hydraulic pressure. In some cases, the membrane is configured so that a larger portion of the inflow solute (e.g., solute ions such as lithium cations) is retained by the membrane compared to a nanofiltration (NF) membrane, thereby reducing the permeate salinity and increasing the retentate outlet salinity. It is believed that, compared to a low rejection nanofiltration membrane, the use of such a membrane can produce a highly concentrated stream because the lower ion permeability improves the degree of separation. However, it has also been recognized in the context of the present disclosure that the performance of at least some membrane-based separation systems is at least partially based on the amount of permeate produced by the membrane under given operating conditions and the degree of separation performed by the membrane. In the context of the present disclosure, the amount of permeate produced at the membrane separator (defined as the percentage calculated by dividing the value of the permeate outlet mass flow rate by the value of the retentate inlet mass flow rate and multiplying by 100) is referred to as "recovery". Also in the context of the present disclosure, the degree of separation is described by the "rejection rate" of the membrane, as explained in more detail below. Typically, for a membrane, an increase in feed salinity results in a reduction in the recovery and rejection rate achieved by the membrane. Reduced recovery and rejection can result in poor membrane performance, and in such cases significantly greater amounts of membrane area may be required to separate certain liquids (eg, desalination of higher salinity water).

[0046] One way to address the above problem is to use a system with multiple stages (e.g., membrane separators) in which the retentate outlet stream from the previous stage is transported to the next stage as the retentate inlet stream for further concentration. At least because water permeability decreases significantly with increasing salinity (or solute concentration), the ability of a given membrane to further concentrate the stream in subsequent stages may become limited. In some embodiments, this potential problem of system performance is at least partially addressed by using membranes with varying (e.g., increasing in some cases) permeability as a function of increasing salinity in a multi-stage system.

[0047] One aspect of the present disclosure relates to recovering lithium from a liquid (e.g., from a liquid stream). Lithium recovery can include obtaining lithium from such a liquid (e.g., as a lithium salt). Lithium recovery can be performed using a lithium recovery system. Figures 1A to 3K , 6A to 6B, and 13A to 15C are schematic diagrams of examples of lithium recovery systems 100 according to certain embodiments. In some embodiments, part or all of the lithium is recovered in the form of a lithium salt in solid form. In some embodiments, part or all of the lithium is recovered in the form of a solution comprising dissolved lithium cations. In some embodiments, part or all of the lithium is recovered in the form of a solution or suspension comprising a relatively high concentration of lithium cations (compared to non-lithium cations).

[0048] In some embodiments, the lithium salt is obtained at least in part by removing at least a portion of the liquid from a feed stream comprising a liquid, dissolved lithium cations, and dissolved non-lithium cations to form a concentrated stream. As described in more detail below, the concentrated stream may be subjected to one or more additional downstream treatments as part of a method for obtaining lithium (e.g., as a lithium salt), such as removal of impurities (e.g., non-lithium cations), anion exchange, and / or solid lithium salt formation (e.g., via precipitation or crystallization). In some embodiments, during the formation of the concentrated stream, at least some of the liquid of the feed stream is removed (e.g., at least 75% by weight, at least 80% by weight, at least, at least 90% by weight, at least 95% by weight, at least 98% by weight, at least 99% by weight, at least 99.9% by weight, or even 100% by weight). In some embodiments, at least some of the liquid is removed from the feed stream via a membrane separator and / or a humidifier, as described in more detail below.

[0049] The methods and systems described herein can be used to process a variety of feed streams. Typically, the feed stream comprises at least one liquid and at least one dissolved substance (also referred to herein as a solute). According to certain embodiments, the feed stream comprises dissolved ions. The dissolved ions can be derived from, for example, a salt dissolved in the liquid of the feed stream. The dissolved ions are typically ions that have been dissolved to the extent that the ions are no longer ionically bonded to the counter ions. As described above, the feed stream may comprise dissolved lithium cations and at least one dissolved non-lithium cation. The dissolved non-lithium cations may be non-lithium monovalent cations (i.e., cations whose redox state is +1 when dissolved). In some embodiments, the non-lithium cations are divalent cations (i.e., cations whose redox state is +2 when dissolved). In some embodiments, the non-lithium cations are selected from sodium cations (Na + ), potassium cation (K + ), magnesium cation (Mg 2+ ) and calcium cation (Ca 2+) in one or more. In addition to dissolved lithium cations and non-lithium cations, the feed stream may also include any of a variety of other dissolved substances. For example, the feed stream may include dissolved anions. The dissolved anions may include monovalent anions (i.e., anions whose redox state is -1 when dissolved) and / or divalent anions (i.e., anions whose redox state is -2 when dissolved). In some embodiments, the feed stream includes anions selected from one or more of chloride, sulfate, carbonate, bicarbonate, nitrate, borate, phosphate, bromide, citrate, oxygen anions, and hydrogen anions. In some embodiments, cations and / or anions with other valence states may also be present in the feed stream (e.g., aqueous feed stream).

[0050] In some embodiments, the total concentration of dissolved ions in the feed stream can be relatively high. An advantage associated with certain embodiments is that an initial feed stream (e.g., an aqueous feed stream) having a relatively high dissolved ion concentration can be subjected to liquid removal (e.g., for lithium concentration) without using energy-intensive desalination methods. In certain embodiments, the total concentration of dissolved ions in the feed stream delivered to the lithium recovery system is at least 1,000 mg / L, at least 5,000 mg / L, at least 10,000 mg / L, at least 12,000 mg / L, at least 14,000 mg / L, and / or up to 50,000 mg / L, up to 60,000 mg / L, up to 100,000 mg / L, up to 500,000 mg / L, or greater.

[0051] According to certain embodiments, the feed stream transported to the lithium recovery system comprises a suspended and / or emulsified immiscible phase. Typically, the immiscible phase of suspension and / or emulsification is a material that is insoluble in water to a degree greater than 10% by weight under the temperature and other conditions of the operating stream. In some embodiments, the immiscible phase of suspension and / or emulsification includes oil and / or grease. The term "oil" generally refers to a fluid that is more hydrophobic than water and is not miscible with water or insoluble in water, as known in the art. Therefore, in some embodiments, oil can be a hydrocarbon, but in other embodiments, oil can include other hydrophobic fluids. In some embodiments, at least 0.1% by weight, at least 1% by weight, at least 2% by weight, at least 5% by weight, or at least 10% by weight of the feed stream (e.g., aqueous feed stream) (and / or, in some embodiments, up to 20% by weight, up to 30% by weight, up to 40% by weight, up to 50% by weight, or more) is composed of a suspended and / or emulsified immiscible phase.

[0052] In some embodiments, the feed stream is treated to remove at least some impurities prior to the liquid removal step described below. For example, impurities such as heavy metals (e.g., iron, aluminum, manganese, barium, strontium) or silicon dioxide can be removed from the feed stream prior to liquid removal (e.g., prior to the membrane-based separation and / or humidifier concentration process described below). In some cases, at least some of these impurities are removed via chemical precipitation. Such chemical precipitation processes may include the addition of reagents including, but not limited to, aluminates (e.g., sodium aluminate), inorganic compounds (e.g., FeCl 3 ), activated alumina, hypochlorite (e.g., sodium hypochlorite), base (e.g., caustic soda (NaOH)), acid and / or polymer. The feed stream may also be fed through one or more ion exchange media, such as ion exchange columns, prior to the liquid removal step described below.

[0053] Although one or more components of the lithium recovery system can be used to separate the immiscible phase of suspension and / or emulsification from the feed stream flowing in, such separation is optional. For example, in some embodiments, the feed stream transported to the lithium recovery system is substantially free of immiscible phases of suspension and / or emulsification. In certain embodiments, one or more separation units upstream of the lithium recovery system can be used to remove at least partially the immiscible phases of suspension and / or emulsification from the feed stream before the feed stream is transported to the components (e.g., membrane separators and / or humidifiers) of the lithium recovery system. For example, the non-limiting examples of such systems are described in International Patent Publication No. WO2015 / 021062, published on February 12, 2015, which is incorporated herein by reference in its entirety for all purposes.

[0054] In some embodiments, the feed stream can be derived from seawater, groundwater, slightly alkaline water and / or the effluent of a chemical process. In some cases, the system and method described herein can be used to recover lithium from an aqueous feed stream derived from such a process stream, and in some cases at least partially desalinate it. As an example, the feed stream can be derived from the water used in some mining methods for exposing water to salt and minerals. As another example, the feed stream can be the product of an ion extraction process from a waste source such as a waste lithium ion battery. In some embodiments, the feed stream is a lithium-containing brine or is derived from a lithium-containing brine. Such brine can be derived from, for example, the Dead Sea in Israel, the Great Salt Lake in the United States, the Lake Sell in the United States, the Clayton Valley in the United States, the Salton Sea in the United States, the Bonneville in the United States, the Suapan in India, the Zabuye in China, the Taijiner in China, the Uyuni Salt Lake in Bolivia, the Salton Sea in the United States, the Murto Salt Lake in Argentina and / or the Atacama Salt Lake in Chile.

[0055] In the feed stream, various types of liquids can also be used. In some embodiments, the liquid of the feed stream comprises water. For example, in some embodiments, at least 10 wt %, at least 25 wt %, at least 50 wt %, at least 75 wt %, at least 90 wt %, at least 95 wt %, at least 98 wt %, at least 99 wt %, at least 99.9 wt % or more (for example, all) of the liquid are water. Other examples of potential liquids of the feed stream include but are not limited to alcohol and / or hydrocarbons. The liquid of the feed stream can be a mixture of different liquid phase materials. For example, the liquid can be a mixture of water and a water-miscible organic liquid such as alcohol.

[0056] Depending on the source of the feed stream and / or the desired application, the feed stream can have any of a variety of dissolved lithium cation concentrations. The versatility of the technology described in the present disclosure can allow lithium to be recovered from a relatively lithium-poor liquid source due to the ability to effectively concentrate the liquid by several orders of magnitude in some embodiments. Alternatively or additionally, the versatility of the technology described in the present disclosure can allow lithium to be recovered from a relatively lithium-rich source due to the ability to remove liquid from a highly concentrated stream with relatively low energy input and / or pressure on system components in some embodiments compared to typical concentration techniques. In some embodiments, the concentration of dissolved lithium cations in the feed stream is greater than or equal to 10 mg / L, greater than or equal to 50 mg / L, greater than or equal to 100 mg / mL, greater than or equal to 200 mg / L, greater than or equal to 500 mg / L, or greater. In some embodiments, the concentration of dissolved lithium cations in the feed stream is less than or equal to 2,000 mg / L, less than or equal to 1,600 mg / mL, less than or equal to 1,200 mg / L, less than or equal to 1,000 mg / L, less than or equal to 800 mg / L, less than or equal to 680 mg / L, less than or equal to 600 mg / L, or lower. Combinations of these ranges (e.g., greater than or equal to 10 mg / L and less than or equal to 2,000 mg / L, or greater than or equal to 10 mg / L and less than or equal to 680 mg / L) are possible. The concentration of one or more dissolved ions (e.g., lithium cations, non-lithium cations, etc.) can be measured according to any method known in the art. For example, suitable methods for measuring the concentration of one or more dissolved ions include inductively coupled plasma (ICP) spectroscopy (e.g., inductively coupled plasma optical emission spectroscopy). As a non-limiting example, an Optima 8300 ICP-OES spectrometer can be used.

[0057] The concentrated stream formed by removing liquid from the feed stream can have a higher concentration of dissolved lithium cations than the feed stream. In the context of the present disclosure, it has been recognized that concentrating lithium cations (e.g., by removing liquid) can promote the effective removal of impurities such as non-lithium cations in some cases. For example, as described below, some embodiments utilize the solubility difference between at least some lithium salts and non-lithium salts. First, achieving a relatively high concentration of dissolved lithium cations (and / or non-lithium cations) can promote such a separation process. Some of the techniques described below (e.g., membrane-based separation, humidification) can achieve lithium cation concentration relatively efficiently in terms of energy and / or operating expenses in some cases. In some embodiments, the ratio of the concentration of dissolved lithium cations in the concentrated stream to the concentration of dissolved lithium cations in the feed stream is greater than or equal to 4, greater than or equal to 5, greater than or equal to 10, greater than or equal to 20, greater than or equal to 25 and / or up to 30, up to 40, up to 50, or greater.

[0058] In some embodiments, the concentrate stream has a relatively high concentration of dissolved lithium cations. For example, in some embodiments, the concentration of dissolved lithium cations of the concentrate stream is greater than or equal to 40 mg / L, greater than or equal to 50 mg / L, greater than or equal to 100 mg / L, greater than or equal to 200 mg / L, greater than or equal to 500 mg / L, greater than or equal to 1,000 mg / L, greater than or equal to 2,000 mg / L, greater than or equal to 5,000 mg / L, greater than or equal to 10,000 mg / L, greater than or equal to 20,000 mg / L, greater than or equal to 30,000 mg / L, and / or up to 50,000 mg / L, or more.

[0059] In some embodiments, at least some of the liquid removed during the removing step (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) is removed using one or more membrane separators. A membrane separator refers to a collection of components comprising one or more semipermeable membranes configured to perform a membrane-based separation process (e.g., an osmotic process, such as a reverse osmosis process, a filtration process, or a combination thereof) on at least one input stream and produce at least one output stream. The membrane separator may include at least one semipermeable membrane that defines a permeate side of a first membrane separator and a retentate side of a first membrane separator. For example, with reference to Figures 1A to 1B, 3A to 3K, 6A to 6B, the lithium recovery system 100 includes a first membrane separator 101 having a retentate side 102 and a permeate side 103, and is arranged so that the membrane separator 101 can receive at least a portion of a feed stream 104. Each membrane separator described herein may include additional subunits, for example, a single semipermeable membrane module (e.g., in the form of a box), a valve, a fluid conduit, etc. As described in more detail below, each membrane separator may include a single semipermeable membrane or multiple semipermeable membranes. In some embodiments, a single membrane separator may include multiple subunits (e.g., multiple modules such as multiple boxes), which may or may not share a common container.

[0060] In some embodiments, a first membrane separator retentate inlet stream (which may include at least a portion of the liquid from the feed stream (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more), optionally along with one or more other streams) is delivered to the retentate side of the first membrane separator such that a first membrane separator retentate outlet stream exits the retentate side of the first membrane separator and the first membrane separator retentate outlet stream has a concentration of dissolved lithium cations that is (e.g., at least 1.03 times, at least 1.035 times, at least 1.05 times, at least 1.10 times, at least 1.25 times, and / or up to 1.40 times, up to 1.50 times, up to 2 times, up to 3 times, up to 4 times, up to 5 times, or more) greater than the concentration of dissolved lithium cations of the first membrane separator retentate inlet stream. For example, again with reference to Figures 1A to 1B , 3A to 3K, 6A to 6B, and 13A to 15C, the first membrane separator 101 may include at least one semipermeable membrane, the at least one semipermeable membrane defining a retentate side 102 and a permeate side 103, and the first membrane separator retentate inlet stream 105 may be delivered to the retentate side 102 so that the first membrane separator retentate outlet stream 106 leaves the retentate side 102. In some embodiments, for example Figures 1A to 1B , 3A to 3K and 6A to 6B, the first membrane separator retentate inlet stream 105 comprises at least a portion of the feed stream 104. According to some embodiments, steps may be performed such that the concentration of dissolved ions (e.g., dissolved lithium cations) of the first membrane separator retentate outlet stream 106 is greater than the concentration of dissolved lithium cations of the first membrane separator retentate inlet stream 105. Unless otherwise expressly stated, references to the amount of a substance (e.g., concentration comparisons) described in this disclosure are based on mass (e.g., concentrations are g / mL, and percentages such as salinity are weight percentages). However, concentration comparisons may also be expressed on an atomic or molar basis.

[0061] In some embodiments, hydraulic pressure is applied (e.g., to facilitate the transport of liquids and / or solutes from the retentate side to the permeate side). In some embodiments, the system is operated so that the hydraulic pressure of the first membrane separator retentate inlet stream is at least 200 psi (at least 1.38×10 3 kPa), at least 500 psi (at least 3.45×10 3 kPa), at least 750 psi (at least 5.17×10 3 kPa), at least 1000 psi (at least 6.90×10 3 kPa) and / or up to 1500 psi (up to 1.03×10 4 kPa), up to 2000 psi (up to 1.38×10 4 kPa), or greater.

[0062] In some embodiments, at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, and / or up to 90 wt%, up to 95 wt%, up to 99 wt%, or more) of the liquid from the retentate inlet stream of the first membrane separator is transported from the retentate side of the first membrane separator through the semipermeable membrane of the membrane separator to the permeate side of the first membrane separator. Figures 1A to 1B , 3A to 3K, 6A to 6B and 13A to 15C, for example, at least a portion of the liquid from the first membrane separator retentate inlet stream 105 can be transported from the retentate side 102 through the semipermeable membrane to the permeate side 103. The liquid transported from the retentate side to the permeate side of the first membrane separator can form the first membrane separator permeate outlet stream (e.g., Figures 1A to 1B , 3A to 3K, 6A to 6B, and 13A to 15C) may be discharged from the system (e.g., as a substantially pure liquid, such as substantially pure water).

[0063] In some, but not necessarily all, embodiments, a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, and / or up to 85 wt%, up to 90 wt%, or more) of the dissolved lithium cations from the first membrane separator retentate inlet stream is transported from the retentate side of the first membrane separator through the semipermeable membrane of the first membrane separator to the permeate side of the first membrane separator. However, in some embodiments, less than or equal to 20 wt%, less than or equal to 10 wt%, less than or equal to 5 wt%, less than or equal to 2 wt%, less than or equal to 1 wt%, less than or equal to 0.1 wt%, or less (e.g., none) of the dissolved lithium cations from the first membrane separator retentate inlet stream is transported from the retentate side of the first membrane separator through the semipermeable membrane of the first membrane separator to the permeate side of the first membrane separator.

[0064] In some, but not necessarily all, embodiments, a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, and / or up to 85 wt%, up to 90 wt%, or more) of any dissolved non-lithium cations present in the first membrane separator retentate inlet stream is transported from the retentate side of the first membrane separator through the semipermeable membrane of the first membrane separator to the permeate side of the first membrane separator. However, in some embodiments, less than or equal to 20 wt%, less than or equal to 10 wt%, less than or equal to 5 wt%, less than or equal to 2 wt%, less than or equal to 1 wt%, less than or equal to 0.1 wt%, or less (e.g., none) of the dissolved non-lithium cations from the first membrane separator retentate inlet stream is transported from the retentate side of the first membrane separator through the semipermeable membrane of the first membrane separator to the permeate side of the first membrane separator.

[0065] In some embodiments, the method of obtaining lithium (e.g., as a lithium salt) is performed such that at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the first membrane separator retentate outlet stream is part of a concentrate stream. Figures 1A to 1B and 13A-13B, at least a portion of the first membrane separator retentate outlet stream 106 is a portion of the concentrate stream 108. Figures 1A to 1B The membrane separator retentate outlet stream 106 is shown to be fed directly to the concentrate stream 108, but other arrangements are possible. For example, in some embodiments, a portion of the first membrane separator retentate outlet stream that ultimately becomes part of the concentrate stream first passes through one or more intermediate processes (e.g., by being conveyed through, for example, Figures 3A to 3K, one or more additional membrane separators and / or humidifiers among 6A to 6B and 14A to 15C).

[0066] In some embodiments, one or more membrane separators (e.g., first membrane separator) operate as a permeation separator. For example, in some embodiments, the semipermeable membrane is a permeation membrane. According to certain embodiments, the permeation membrane of the permeation unit can be transported through a transmembrane net driving force (i.e., a net driving force across the thickness of the membrane) to achieve. Typically, the transmembrane net driving force (Δχ) is expressed as:

[0067] Δχ=ΔP-ΔΠ=(P 1 -P 2 )-(Π 1 -Π 2 ) [1]

[0068] Among them, P 1 is the hydraulic pressure on the retentate side of the membrane, P 2 is the hydraulic pressure on the permeate side of the membrane, Π 1 is the osmotic pressure of the stream on the retentate side of the membrane, and 2 is the osmotic pressure of the flow on the permeate side of the membrane. (P 1 -P 2 ) can be called the transmembrane hydraulic pressure difference, and (Π 1 -Π 2 ) can be called the transmembrane osmotic pressure difference.

[0069] Those of ordinary skill in the art are familiar with the concept of osmotic pressure. The osmotic pressure of a particular liquid is an inherent property of the liquid. Osmotic pressure can be determined in a variety of ways, the most effective of which depends on the type of liquid being analyzed. For solutions with relatively low ion molar concentrations, osmotic pressures can be accurately measured using an osmometer. In other cases, osmotic pressure can be determined simply by comparing with a solution with a known osmotic pressure. For example, in order to determine the osmotic pressure of an uncharacterized solution, a known amount of an uncharacterized solution can be applied to one side of a nonporous semipermeable osmotic membrane, and different solutions with known osmotic pressures can be repeatedly applied to the other side of the osmotic membrane until the pressure differential across the thickness of the membrane is zero.

[0070] The osmotic pressure (Π) of a solution containing n dissolved species can be estimated as:

[0071]

[0072] Among them, i j is the van't Hoff coefficient of the jth dissolved substance, M jis the molar concentration of the jth dissolved species in the solution, R is the ideal gas constant, and T is the absolute temperature of the solution. For liquids with low dissolved species concentrations (e.g., concentrations between about 4 wt % and about 6 wt % or less), Equation 2 generally provides an accurate estimate of osmotic pressure. For many liquids containing dissolved species, the increase in osmotic pressure with increasing salt concentration is greater than linear (e.g., slightly exponential) at concentrations of the species above about 4 wt % to 6 wt %.

[0073] As described above, according to some embodiments, one type of osmotic separation technology that can be performed using the membrane separator of the present disclosure is reverse osmosis. Reverse osmosis generally occurs when the osmotic pressure on the retentate side of the osmotic membrane is greater than the osmotic pressure on the permeate side of the osmotic membrane, and pressure is applied to the retentate side of the osmotic membrane so that the hydraulic pressure on the retentate side of the osmotic membrane is sufficiently greater than the hydraulic pressure on the permeate side of the osmotic membrane, so that the osmotic pressure difference is overcome, and a solvent (e.g., water) is transported from the retentate side of the osmotic membrane to the permeate side of the osmotic membrane. Generally, when the transmembrane pressure difference (P 1 -P 2 ) is greater than the transmembrane osmotic pressure difference (Π 1 -Π 2 ), a situation is created whereby liquid (e.g., water) is transported from the retentate side of the osmotic membrane to the permeate side of the osmotic membrane (rather than liquid being transported from the permeate side of the osmotic membrane to the first side of the osmotic membrane, which is more energetically favorable when no pressure is applied to the retentate side of the osmotic membrane).

[0074] In some embodiments, some or all of the membrane separators in the lithium recovery system are configured and operated to perform reverse osmosis (eg, during a process to obtain lithium). For example, in some embodiments, the first membrane separator is operated to perform reverse osmosis.

[0075] In some embodiments, at least a portion of the flow leaving one or more membrane separators is recycled and fed back into the same membrane separator. Compared to some embodiments without such recycling, such recycling process can allow a relatively large amount of liquid to be removed by the membrane separator before further downstream processes (in some cases, using fewer system components).

[0076] As an example of a recycling process, in some embodiments, the first membrane separator retentate inlet stream comprises at least a portion of the first membrane separator retentate outlet stream (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more). As part of the methods described in the present disclosure, during at least a period of time (e.g., all of the time or a subset of the time) during operation of the first membrane separator, the first membrane separator retentate inlet stream may comprise at least a portion of the first membrane separator retentate outlet stream. As an illustrative example, Figure 1B The illustrated embodiment shows that a portion of the first membrane separator retentate outlet stream 106 is conveyed back to the first membrane separator retentate inlet stream 105 as a recycle stream 109. The recycle stream 109 can be combined with the feed stream 104 to form at least a portion of the first membrane separator retentate inlet stream 105. However, in some embodiments, such as during certain batch processes described below, the recycle stream comprising at least a portion of the first membrane separator retentate outlet stream is not mixed with the feed stream before or during incorporation of a portion of the first membrane separator retentate outlet stream into the first membrane separator retentate inlet stream. For example, in some embodiments, during at least a period of time during the liquid removal process, the first membrane separator retentate inlet stream includes at least a portion of the first membrane separator retentate outlet stream, but during this period of time, less than or equal to 20 weight percent, less than or equal to 10 weight percent, less than or equal to 5 weight percent, less than or equal to 2 weight percent, less than or equal to 1 weight percent, less than or equal to 0.1 weight percent, or no first membrane separator retentate inlet stream is from the feed stream.

[0077] During the recycling process, according to some embodiments, at least some (or all) of the rest of the first membrane separator retentate outlet flow that is not recycled back to the retentate side of the membrane separator can become a part (or all) of the concentrated flow. In some embodiments, the hydraulic pressure of the recirculating flow increases (e.g., increases by at least 5%, at least 10%, at least 20%, at least 50%, at least 80%, at least 90%, at least 95%, at least 99%, or more) before becoming a part of the first membrane separator retentate inlet flow. Such a pressure increase can be achieved using any of a variety of techniques, such as using a pump. In some cases, the recycling process involving the first membrane separator (e.g., a portion of the first membrane separator retentate outlet flow is incorporated into the first membrane separator retentate inlet flow) is performed in batch mode. In some embodiments, the recycling process is performed in a continuous manner. In some embodiments, the recycling process is performed using a semi-batch process. Batch operation, semi-batch operation and continuous operation of membrane separators are generally known. During batch operation, as a large amount of flow is fed to the retentate side inlet flow, the hydraulic pressure of the membrane separator retentate inlet flow increases over time during operation. In the context of the present disclosure, it has been recognized that batch or semi-batch operation of a process (e.g., a recycling process) involving a membrane separator can reduce the amount of energy required to operate the membrane separator by gradually increasing the concentration (and in some cases, the hydraulic pressure) of the membrane separator retentate inlet flow, rather than maintaining the flow of all membrane separators at high pressure as is usually the case during continuous operation. Compared with typical existing lithium recovery technologies, such a reduction in energy use can allow lithium recovery to have higher energy efficiency and / or lower cost.

[0078] In some embodiments, at least some (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the liquid removed from the feed stream during the removal step is performed using one or more humidifiers. The humidifier can have any configuration that allows the generation of a gaseous stream containing a vapor (e.g., water vapor) transferred from a liquid stream (e.g., a stream containing liquid water) via an evaporation process. In some embodiments, the humidifier is configured to generate such a gaseous stream containing vapor (e.g., "humidified gas stream") by transferring the vapor (e.g., water vapor) from a liquid stream (e.g., a stream containing liquid water) to a carrier gas via an evaporation process. In some embodiments, the humidifier includes a liquid inlet configured to receive a liquid stream and / or a gas inlet configured to receive a carrier gas. The humidifier may also include a liquid outlet and / or a gas outlet. In certain embodiments, the carrier gas includes a non-condensable gas. Non-limiting examples of suitable non-condensable gases include air, nitrogen, oxygen, helium, argon, carbon monoxide, carbon dioxide, sulfur oxides (SOx )(For example, SO 2 、SO 3 ) and / or nitrogen oxides (NO x )(e.g., NO, NO 2 ). Examples of potentially suitable humidifiers include, but are not limited to, bubble column humidifiers and packed bed humidifiers, further details of which are provided below.

[0079] In some embodiments, the process of removing liquid from the feed stream includes delivering a humidifier liquid inlet stream comprising at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the feed stream to the humidifier (e.g., via a humidifier liquid inlet). Figure 2A A schematic diagram of one embodiment of a lithium recovery system 100 including a humidifier 117 is shown. Figure 2A In the illustrated embodiment, at least a portion of the feed stream 104 forms some (e.g., at least 5 weight percent, at least 10 weight percent, at least 20 weight percent, at least 50 weight percent, at least 80 weight percent, at least 90 weight percent, at least 95 weight percent, at least 99 weight percent, or more) or all of the humidifier liquid inlet stream 118.

[0080] In some embodiments, at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the liquid of the humidifier liquid inlet stream is caused to evaporate within the humidifier (e.g., within the container of the humidifier) ​​to produce a humidified gas stream and a humidifier liquid outlet stream. Referring again to Figure 2A For example, at least a portion of the liquid of humidifier liquid inlet stream 118 can be caused to evaporate within humidifier 117 to produce humidified gas stream 119 (including at least a portion of the vapor produced by evaporation) and humidifier liquid outlet stream 120. In some cases, the humidified gas stream is produced by delivering a gas stream (e.g., including a carrier gas) to the humidifier (e.g., via a humidifier gas inlet) and transferring at least some of the vapor formed by evaporation into the gas stream. For example, Figure 2B Gas stream 121 is shown entering humidifier 117 , where a carrier gas of gas stream 121 may contact liquid of humidifier liquid inlet stream 118 , thereby transferring liquid (eg, in vapor form) to the gas stream to form humidified gas stream 119 .

[0081] The humidifier liquid outlet stream can have a higher concentration of dissolved lithium cations than the humidifier liquid inlet stream. In some embodiments, the concentration of dissolved lithium cations of the humidifier liquid outlet stream is at least 1.03 times, at least 1.05 times, at least 1.1 times, at least 1.2 times, at least 1.25 times, and / or up to 1.5 times, up to 2 times, up to 4 times, up to 5 times, or more times higher than the concentration of dissolved lithium cations of the humidifier liquid inlet stream. As described above, increasing the concentration of dissolved lithium ions can facilitate downstream separation processes, such as processes involving removal of non-lithium cations (e.g., by selective thermal precipitation).

[0082] In some embodiments, the method of obtaining lithium (e.g., as a lithium salt) is performed such that at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the humidifier liquid outlet stream is part of a concentrate stream. Figures 2A to 3B 6A-6B, at least a portion of the humidifier liquid outlet stream 120 is a portion of the concentrate stream 108. Figures 2A to 3B 6A-6B show that the humidifier liquid outlet stream 120 is fed directly to the concentrate stream 108, but other arrangements are possible. In some embodiments, a portion of the membrane separator retentate outlet stream that ultimately becomes part of the concentrate stream first passes through one or more intermediate processes (e.g., by being sent through one or more additional humidifiers and / or membrane separators).

[0083] In some embodiments, the humidifier is part of a humidification-dehumidification (HDH) device, which also includes a dehumidifier. In some embodiments, the process of removing liquid from the feed stream also includes condensing at least a portion of the liquid in the humidified gas (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) in the dehumidifier to produce a condensed liquid stream. The dehumidifier can be configured to receive the humidified gas stream from the humidifier. In some embodiments where the liquid includes water, the dehumidifier can be configured to transfer at least a portion of the water (e.g., water vapor) from the humidified gas stream to a substantially pure water stream through a condensation process, thereby producing a substantially pure water stream. Figures 2B to 3BIn 6A to 6B, the lithium recovery system 100 includes a dehumidifier 122, which is configured to receive (e.g., via another fluid conduit) at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the humidified gas stream 119. The condensed liquid from the humidified gas stream 119 produced in the dehumidifier 122 can form a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the condensed liquid stream 123 (e.g., substantially pure water). Any of a variety of dehumidifiers can be used. For example, the dehumidifier can include a bubble tower dehumidifier, which is described in more detail below. It has been appreciated that some such configurations involving coupling a dehumidifier to a humidifier during at least a portion of lithium recovery can allow for the production of commercially valuable resources, such as substantially pure water, while (or subsequently thereto) obtaining lithium (e.g., lithium salts). In addition, such configurations can allow for the recovery of at least a portion of the energy used to remove liquid from a feed stream. Such processes can help to obtain greater commercial value from the recovery of lithium from certain feed stream sources (e.g., brine) compared to typical lithium recovery techniques.

[0084] In some embodiments, the process of removing liquid from a feed stream (e.g., comprising liquid, dissolved lithium cations, and dissolved non-lithium cations) is performed using both a membrane separator and a humidifier. In some embodiments, the first membrane separator and the humidifier fluid are arranged in series. For example, in some embodiments, the humidifier liquid inlet stream comprises at least a portion of the first membrane separator retentate outlet stream (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more). As an illustrative example, Figure 3AAn embodiment of a lithium recovery system 100 is shown in which at least a portion of a membrane separator retentate outlet stream 106 (comprising at least a portion of a feed stream 104 processed in a first membrane separator 101) is diverted to a humidifier 117 (e.g., via one or more conduits) by forming a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) or all of a humidifier liquid inlet stream 118. In the context of the present disclosure, it is recognized that in some cases, processes involving removal of liquid by membrane-based (e.g., osmosis) separation followed by humidification can achieve ion concentration (e.g., lithium cation concentration) to a greater extent and / or with greater efficiency than can be achieved with either technique alone. For example, a membrane-based separation process can be well suited to concentrating an initial feed stream from, for example, brine. Such a feed stream based on membrane concentration can produce a relatively high concentration of dissolved ions, which is more suitable for further concentration using a humidifier compared to other membrane-based separations. For example, as the ion concentration increases, reverse osmosis may require more and more hydraulic pressure, thereby requiring more and more energy consumption and / or equipment wear. It has been realized that in the case of a higher concentration of ions, it may not be necessary to experience the same adverse effects by concentrating via a humidifier. In addition, the viscosity of the stream with a higher concentration of dissolved substances is often greater than that of the stream with a relatively low concentration of dissolved substances. In the context of the present disclosure, it is observed that in some cases, a humidifier is more suitable for more viscous solutions than a membrane-based (permeation) system. In addition, the flux of a stream with a higher concentration of dissolved substances in a membrane-based (e.g., permeation) system tends to decrease, partly due to higher viscosity and / or increased concentration polarization. Therefore, the initial concentration process with a membrane-based system and the further concentration of the more concentrated output (with a higher viscosity) with a humidifier can reduce or avoid such adverse effects compared to further concentration with a membrane-based system.

[0085] Although the above disclosure describes a series configuration of a first membrane separator and a humidifier, other arrangements are possible. For example, in some embodiments, the first membrane separator and the humidifier are arranged in parallel so that (a) the first membrane separator retentate inlet stream comprises a first portion of the feed stream, and (b) the humidifier liquid inlet stream comprises a second portion of the feed stream. In some embodiments, a concentrate stream is produced at least in part by combining at least a portion of the first membrane separator retentate outlet stream (and / or the second membrane separator retentate outlet stream described below) and at least a portion of the humidifier liquid outlet stream.

[0086] Although in some embodiments, the methods described herein employ a single membrane separator for removing liquid from a feed stream (e.g., Figure 1A , 3A and 13A to 13B), but in some embodiments, multiple membrane separators are used. For example, a second membrane separator can be used to further remove liquid from one or more streams. In some cases, the use of a first membrane separator and a second membrane separator can provide tunability of the flow rate and hydraulic pressure of each membrane separator based on, for example, the ion concentration of the stream fed to each unit, thereby facilitating the effective removal of liquid from the feed stream. In some embodiments, the method for removing liquid from the feed stream also includes conveying a second membrane separator retentate inlet stream containing at least a portion of the first membrane separator retentate outlet stream to the retentate side of the second membrane separator. The second membrane separator may include at least one semipermeable membrane, the semipermeable membrane defining the permeate side of the second membrane separator and the retentate side of the second membrane separator.

[0087] In some embodiments, a second membrane separator retentate inlet stream (which may include at least a portion (e.g., at least 5 wt %, at least 10 wt %, at least 20 wt %, at least 50 wt %, at least 80 wt %, at least 90 wt %, at least 95 wt %, at least 99 wt %, or more) of the liquid from the first membrane separator retentate outlet stream (and, in some cases, one or more other streams) is delivered to the retentate side of the second membrane separator such that the second membrane separator retentate outlet stream exits the retentate side of the second membrane separator, and the second membrane separator retentate outlet stream The concentration of dissolved lithium cations in the second membrane separator retentate inlet stream is (e.g., at least 1.03 times, at least 1.035 times, at least 1.05 times, at least 1.10 times, at least 1.25 times, and / or up to 1.40 times, up to 1.50 times, up to 2 times, up to 3 times, up to 4 times, up to 5 times, up to 6 times, or more) greater than the concentration of dissolved lithium cations in the second membrane separator retentate inlet stream. In some embodiments, the second membrane separator retentate inlet stream comprises at least a portion of the feed stream (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 30 wt%, at least 50 wt%, at least 60 wt%, at least 5 ... 50 wt %, at least 80 wt %, at least 90 wt %, at least 95 wt %, at least 99 wt %, or more), optionally with one or more other streams. Having the retentate side of the second membrane separator receive at least a portion of the feed stream can help process a feed stream having a higher osmotic pressure and / or a higher dissolved lithium cation concentration than in some cases where the feed stream is fed to the retentate side of the first membrane separator. The second membrane separator inlet stream containing at least a portion of the feed stream (and in some cases, at least a portion of the first membrane separator retentate outlet stream) can be delivered to the first membrane separator. The retentate side of the second membrane separator is such that the second membrane separator retentate outlet stream leaves the retentate side of the second membrane separator, and the osmotic pressure and / or dissolved lithium cation concentration of the second membrane separator retentate outlet stream is (e.g., at least 1.03 times, at least 1.035 times, at least 1.05 times, at least 1.10 times, at least 1.25 times and / or up to 1.40 times, up to 1.50 times, up to 2 times, up to 3 times, up to 4 times, up to 5 times, or more times) the osmotic pressure and / or dissolved lithium cation concentration of the second membrane separator retentate inlet stream. For example, with reference to Figures 3B to 3K , 6B and 14A to 15C, the second membrane separator 110 may include at least one semipermeable membrane, the at least one semipermeable membrane defining a retentate side 111 and a permeate side 112, and the second membrane separator retentate inlet stream 113 may be delivered to the retentate side 111 so that the second membrane separator retentate outlet stream 114 leaves the retentate side 111. In some embodiments, for example Figures 3B to 3K, 6B and 14A to 15C, the second membrane separator retentate inlet stream 113 comprises at least a portion of the first membrane separator retentate outlet stream 106. In some embodiments, for example Figures 14A to 14D Those shown, the second membrane separator retentate inlet stream 113 comprises at least a portion of the feed stream 104. Steps may be performed such that the concentration of dissolved lithium cations of the second membrane separator retentate outlet stream 114 is greater than the concentration of dissolved lithium cations in the second membrane separator retentate inlet stream 113. In some embodiments, hydraulic pressure is applied (e.g., to facilitate transport of liquids and / or solutes from the retentate side to the permeate side). In some embodiments, the system is operated such that the hydraulic pressure of the second membrane separator retentate inlet stream is at least 50%, at least 75%, at least 90%, at least 95%, or greater than the pressure of the first membrane separator retentate inlet stream. In some embodiments, the system is operated such that the hydraulic pressure of the second membrane separator retentate inlet stream is at least 200 psi (at least 1.38×10 3 kPa), at least 500 psi (at least 3.45×10 3 kPa), at least 750 psi (at least 5.17×10 3 kPa), at least 1000 psi (at least 6.90×10 3 kPa) and / or up to 1500 psi (up to 1.03×10 4 kPa), up to 2000 psi (up to 1.38×10 4 kPa), or greater.

[0088] In some embodiments, at least a portion (e.g., at least 5 wt %, at least 10 wt %, at least 20 wt %, at least 50 wt %, at least 80 wt %, and / or up to 90 wt %, up to 95 wt %, up to 99 wt %, or more) of the liquid from the retentate inlet stream of the second membrane separator is transported from the retentate side of the second membrane separator through the semipermeable membrane of the second membrane separator to the permeate side of the second membrane separator. Figures 3B to 3K , 6B and 14A to 15C, for example, at least a portion of the liquid from the second membrane separator retentate inlet stream 113 can be transported from the retentate side 111 through the semipermeable membrane to the permeate side 112. The liquid transported from the retentate side to the permeate side of the second membrane separator can form the second membrane separator permeate outlet stream (e.g., Figures 3B to 3K, 6B and 14A to 15C) of the second membrane separator permeate outlet stream 115) (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt% or more) or all. The second membrane separator permeate outlet stream can be recirculated to an earlier stream in the system. For example, in some embodiments, the first membrane separator retentate inlet stream includes at least a portion of the second membrane separator permeate outlet stream (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt% or more).

[0089] In some embodiments, at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, and / or up to 85 wt%, up to 90 wt%, or more) of the dissolved lithium cations from the second membrane separator retentate inlet stream is transported from the retentate side of the second membrane separator through the semipermeable membrane of the second membrane separator to the permeate side of the second membrane separator. Figures 3B to 3K , 6B and 14A to 15C, for example, at least a portion of the dissolved lithium cations from the second membrane separator retentate inlet stream 113 can be transported from the retentate side 111 to the permeate side 112 through the semipermeable membrane.

[0090] In some embodiments, at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, and / or up to 85 wt%, up to 90 wt%, or more) of the dissolved non-lithium cations from the second membrane separator retentate inlet stream is transported from the retentate side of the second membrane separator through the semipermeable membrane of the second membrane separator to the permeate side of the second membrane separator. Figures 3B to 3K , 6B and 14A to 15C, for example, at least a portion of any dissolved non-lithium cations in the second membrane separator retentate inlet stream 113 can be transported from the retentate side 111 to the permeate side 112 through the semipermeable membrane.

[0091] The dissolved lithium cations and / or non-lithium cations transported from the retentate side to the permeate side of the second membrane separator can form a second membrane separator permeate outlet stream (e.g., Figures 3B to 3K , 6B and 14A to 15C) in the second membrane separator permeate outlet stream 115) or a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of any solute present in the second membrane separator permeate outlet stream 115.

[0092] The amount of solutes (e.g., lithium cations, non-lithium cations) that pass through the semipermeable membrane of a membrane separator (e.g., a first membrane separator and / or a second membrane separator) can depend on any of a variety of parameters such as the solute concentration in the membrane separator retentate inlet stream, the solute permeability of the membrane, the water permeability of the membrane, the temperature, and / or the hydraulic magnitude of the membrane separator retentate inlet stream. In some embodiments, at least a portion of the liquid and dissolved lithium cations (and in some cases, dissolved non-lithium cations) from the second membrane separator retentate inlet stream is transported from the retentate side of the second membrane separator through the semipermeable membrane of the second membrane separator to the permeate side of the second membrane separator.

[0093] In some embodiments, the method of obtaining lithium (e.g., as a lithium salt) is performed such that at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the second membrane separator retentate outlet stream is part of the concentrate stream. Figure 3B In the embodiment of the present invention, at least a portion of the second membrane separator retentate outlet stream 114 is a portion of the concentrate stream 108 after treatment in the humidifier 117. Figure 3B The second membrane separator retentate outlet stream 114 is shown being fed indirectly to the concentrate stream 108, but other arrangements are possible. For example, in some embodiments, the second membrane separator retentate outlet stream is fed directly to the concentrate stream.

[0094] In some embodiments where one or more membrane separators and a humidifier are arranged in series, a second membrane separator is employed such that the humidifier liquid inlet stream comprises at least a portion (e.g., at least 5 wt %, at least 10 wt %, at least 20 wt %, at least 50 wt %, at least 80 wt %, at least 90 wt %, at least 95 wt %, at least 99 wt %, or more) of the second membrane separator retentate outlet stream. For example, Figure 3B An embodiment of a lithium recovery system 100 is shown in which at least a portion of the second membrane separator retentate outlet stream 114 is diverted to a humidifier 117 by forming a portion (e.g., at least 5 weight percent, at least 10 weight percent, at least 20 weight percent, at least 50 weight percent, at least 80 weight percent, at least 90 weight percent, at least 95 weight percent, at least 99 weight percent, or more) or all of the humidifier liquid inlet stream 118.

[0095] It should be understood that although Figure 3B An embodiment in which the system 100 includes a first membrane separator 101, a second membrane separator 110, and a humidifier 117 is shown, but the presence of a humidifier in a system including a first membrane separator and a second membrane separator is not required. Figure 3CShown includes Figure 3B Schematic diagram of a system 100 in which a first membrane separator 101 and a second membrane separator 110 are configured in the same manner in the embodiment shown. In some embodiments, as Figure 3C The system 100 shown in FIG. 1 can be used to form a concentrate stream 108 that comprises at least a portion (e.g., at least 5 wt. %, at least 10 wt. %, at least 20 wt. %, at least 50 wt. %, at least 80 wt. %, at least 90 wt. %, at least 95 wt. %, at least 99 wt. %, or more) of the second membrane separator retentate outlet stream 114 and has a higher dissolved lithium ion concentration than the feed stream 104. In some embodiments, the concentrate stream from Figure 3C At least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the concentrate stream 108 is subjected to further processing (e.g., by removing at least some of any non-lithium cations present in the concentrate stream, as described elsewhere in this disclosure). In some embodiments, at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the concentrate stream 108 is directly used in any of a variety of desired applications. Such desired applications include, but are not limited to, the production of metallic lithium, use as a desiccant, the production of pyrotechnic products, and the production of medical preparations (e.g., lithium-containing medicaments).

[0096] Some embodiments include delivering the third membrane separator retentate inlet stream to the retentate side of the third membrane separator.The third membrane separator may include at least one semipermeable membrane defining a permeate side of the third membrane separator and a retentate side of the third membrane separator.

[0097] In some embodiments, a third membrane separator retentate inlet stream (which may comprise at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the second membrane separator retentate outlet stream, optionally along with one or more other streams) is conveyed to the retentate side of the third membrane separator such that the third membrane separator retentate outlet stream leaves the retentate side of the third membrane separator, and the concentration of dissolved lithium cations of the third membrane separator retentate outlet stream is (e.g., at least 1.03 times, at least 1.035 times, at least 1.05 times, at least 1.10 times, at least 1.25 times and / or up to 1.40 times, up to 1.50 times, up to 2 times, up to 3 times, up to 4 times, up to 5 times, or more) the concentration of dissolved lithium cations of the third membrane separator retentate inlet stream. In some embodiments, the third membrane separator retentate inlet stream comprises at least a portion of the feed stream (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more), optionally with one or more other streams. Allowing the retentate side of the third membrane separator to receive at least a portion of the feed stream can help process feed streams having higher osmotic pressures and / or dissolved lithium cation concentrations than in some cases where the feed stream is fed to the retentate side of the first membrane separator. A third membrane separator inlet stream comprising at least a portion of the feed stream (in some cases, at least a portion of the second membrane separator retentate outlet stream) can be delivered to the retentate side of the third membrane separator such that the third membrane separator retentate outlet stream exits the retentate side of the third membrane separator, and the osmotic pressure and / or dissolved lithium cation concentration of the third membrane separator retentate outlet stream is (e.g., at least 1.03 times, at least 1.035 times, at least 1.05 times, at least 1.10 times, at least 1.25 times and / or up to 1.40 times, up to 1.50 times, up to 2 times, up to 3 times, up to 4 times, up to 5 times, or more times) the osmotic pressure and / or dissolved lithium cation concentration of the third membrane separator retentate inlet stream. For example, in Figures 3D to 3G , 3K, and 14A to 15C, the third membrane separator 139 may include at least one semipermeable membrane defining a retentate side 140 and a permeate side 141, and a third membrane separator retentate inlet stream 142 may be delivered to the retentate side 140 such that a third membrane separator retentate outlet stream 143 exits the retentate side 140. In some embodiments, for example Figures 3D to 3G , 3K and those shown in 14A to 15C, the third membrane separator retentate inlet stream 142 comprises at least a portion of the second membrane separator retentate outlet stream 114. In some embodiments, for example Figures 15A to 15C , the third membrane separator retentate inlet stream 142 comprises at least a portion of the feed stream 104. According to some embodiments, this step can be performed so that the concentration of dissolved lithium cations of the third membrane separator retentate outlet stream 143 is greater than the concentration of dissolved lithium cations in the third membrane separator retentate inlet stream 142. For example, this step can be performed so that the concentration of dissolved lithium cations of the third membrane separator retentate outlet stream 143 is increased relative to the concentration of dissolved lithium cations in the third membrane separator retentate inlet stream 142 (e.g., at least 1.03 times, at least 1.035 times, at least 1.05 times, at least 1.10 times, at least 1.25 times and / or up to 1.40 times, up to 1.50 times, up to 2 times, up to 3 times, up to 4 times, up to 5 times or more). In some embodiments, hydraulic pressure is applied (e.g., to facilitate the transport of liquids and / or solutes from the retentate side to the permeate side). In some embodiments, the system is operated such that the hydraulic pressure of the third membrane separator retentate inlet stream is at least 50%, at least 75%, at least 90%, at least 95% or more of the pressure of the second membrane separator retentate inlet stream. In some embodiments, the system is operated such that the hydraulic pressure of the third membrane separator retentate inlet stream is at least 200 psi (at least 1.38×10 3 kPa), at least 500 psi (at least 3.45×10 3 kPa), at least 750 psi (at least 5.17×10 3 kPa), at least 1000 psi (at least 6.90×10 3 kPa) and / or up to 1500 psi (up to 1.03×10 4 kPa), up to 2000 psi (up to 1.38×10 4 kPa), or greater.

[0098] In some embodiments, at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, and / or up to 90 wt%, up to 95 wt%, up to 99 wt%, or more) of the liquid from the retentate inlet stream of the third membrane separator is transported from the retentate side of the third membrane separator through the semipermeable membrane of the third membrane separator to the permeate side of the third membrane separator. Figures 3D to 3G , 3K and 14A to 15C, for example, at least a portion of the liquid from the third membrane separator retentate inlet stream 142 can be transported from the retentate side 140 through the semipermeable membrane to the permeate side 141. The liquid transported from the retentate side to the permeate side of the third membrane separator can form a third membrane separator permeate outlet stream (e.g., Figures 3D to 3G, 3K and 14A to 15C) of the third membrane separator permeate outlet flow 144) or a portion (e.g., at least 5 wt. %, at least 10 wt. %, at least 20 wt. %, at least 50 wt. %, at least 80 wt. %, at least 90 wt. %, at least 95 wt. %, at least 99 wt. %, or more) of the liquid.

[0099] In some embodiments, at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, and / or up to 85 wt%, up to 90 wt%, or more) of the dissolved lithium cations from the retentate inlet stream of the third membrane separator is transported from the retentate side of the third membrane separator through the semipermeable membrane of the third membrane separator to the permeate side of the third membrane separator. Figures 3D to 3G , 3K and 14A to 15C, for example, at least a portion of the dissolved lithium cations from the third membrane separator retentate inlet stream 142 can be transported from the retentate side 140 to the permeate side 141 through the semipermeable membrane.

[0100] In some embodiments, at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, and / or up to 85 wt%, up to 90 wt%, or more) of the dissolved non-lithium cations from the third membrane separator retentate inlet stream is transported from the retentate side of the third membrane separator through the semipermeable membrane of the third membrane separator to the permeate side of the third membrane separator. Figures 3D to 3G , 3K and 14A to 15C, for example, at least a portion of any dissolved non-lithium cations in the third membrane separator retentate inlet stream 142 can be transported from the retentate side 140 through the semipermeable membrane to the permeate side 141. The dissolved lithium cations and / or non-lithium cations transported from the retentate side of the third membrane separator to the permeate side can form the third membrane separator permeate outlet stream (e.g., Figures 3D to 3G , 3K and 14A to 15C) in the third membrane separator permeate outlet stream 144) or a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of any solute present in the permeate outlet stream 144.

[0101] The amount of solutes that pass through the semipermeable membrane of the third membrane separator can depend on a variety of parameters such as the solute concentration in the third membrane separator retentate inlet stream, the solute permeability of the membrane, the water permeability of the membrane, the temperature, and / or any one of the hydraulic magnitudes of the third membrane separator retentate inlet stream. In some embodiments, at least a portion of the liquid and solutes from the third membrane separator retentate inlet stream are transported from the retentate side of the third membrane separator through the semipermeable membrane of the third membrane separator to the permeate side of the third membrane separator.

[0102] In some embodiments, the method of obtaining lithium (e.g., as a lithium salt) is performed so that at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the third membrane separator retentate outlet stream is part of the concentrate stream. For example, at least a portion of the third membrane separator retentate outlet stream can be part of the concentrate stream 108 after treatment in a humidifier. However, in some embodiments, the second membrane separator retentate outlet stream is fed directly to the concentrate stream.

[0103] In some embodiments where one or more membrane separators and a humidifier are arranged in series, a third membrane separator is employed such that the humidifier liquid inlet flow includes at least a portion (e.g., at least 5 weight percent, at least 10 weight percent, at least 20 weight percent, at least 50 weight percent, at least 80 weight percent, at least 90 weight percent, at least 95 weight percent, at least 99 weight percent, or more) of the third membrane separator retentate outlet flow.

[0104] Although Figures 1A to 1B , 3A to 3K, 6A to 6B, and 14A to 15C show one, two, or three membrane separators, but it should be understood that different numbers of membrane separators can be applied to the system of the present disclosure and used in the method of the present disclosure. For example, a system including a plurality of membrane separators can have at least one, at least two, at least three, at least four, at least five, at least ten, and at least twenty or more membrane separators configured as described in the present disclosure.

[0105] In some embodiments, at least a portion of the flow leaving one or more membrane separators is recycled and fed back into the membrane separator (e.g., upstream membrane separator). Such a recycling process can allow a relatively large amount of liquid to be removed by the system (in some cases using fewer system components) and / or allow a relatively high recovery rate and / or efficiency compared to some embodiments that do not perform such recycling.

[0106] As an example of a recycling process, in some embodiments, the first membrane separator retentate inlet stream includes at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%) or all of the second membrane separator retentate outlet stream. During at least a period of time (e.g., all of the time or a subset of the time) during operation of the first membrane separator and the second membrane separator as part of the method described in the present disclosure, the first membrane separator retentate inlet stream may include at least a portion of the second membrane separator permeate outlet stream. As an illustrative example, Figure 3E , 3G , 14B, 14D, 15A and 15C show that at least a portion of the second membrane separator permeate outlet stream 115 is transported back to the first membrane separator retentate inlet stream 105. The second membrane separator permeate outlet stream 115 can be combined with the feed stream 104 to form at least a portion of the first membrane separator retentate inlet stream 105.

[0107] As another example of a recycling process, in some embodiments employing a third membrane separator, the second membrane separator retentate inlet stream comprises at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%) or all of the third membrane separator permeate outlet stream. During at least a period of time (e.g., all of the time or a subset of the time) during operation of the first membrane separator, the second membrane separator, and / or the third membrane separator as part of the method described in the present disclosure, the second membrane separator retentate inlet stream may comprise at least a portion of the third membrane separator permeate outlet stream. As an illustrative example, Figure 3E The embodiment shown in shows at least a portion of the third membrane separator permeate outlet stream 144 being conveyed back to the second membrane separator retentate inlet stream 113 . Fig. 14B and 15A Similarly shown is at least a portion of the third membrane separator permeate outlet stream 144 being conveyed back to the second membrane separator retentate inlet stream 113. The third membrane separator permeate outlet stream 144 can be combined with the first membrane separator retentate outlet stream 106 to form at least a portion of the second membrane separator retentate inlet stream 113.

[0108] Other recycling processes may also be used. For example, in some embodiments, the first membrane separator retentate inlet stream contains at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%) or all of the third membrane separator permeate outlet stream. In embodiments where the retentate side of the first membrane separator is fluidly connected to the permeate side of the third membrane separator, such a process may occur. As an illustrative example, Figures 3F to 3G , 14C to 14D and 15B to 15C show that at least a portion of the third membrane separator permeate outlet stream 144 is transported back to the first membrane separator retentate inlet stream 105. The third membrane separator permeate outlet stream 144 can be combined with the feed stream 104 to form at least a portion of the first membrane separator retentate inlet stream 105.

[0109] In some embodiments, the first membrane separator retentate inlet stream comprises at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%) or all of the second membrane separator permeate outlet stream, and also comprises at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%) or all of the third membrane separator permeate outlet stream. In an embodiment where the retentate side of the first membrane separator is fluidly connected to the permeate side of the second membrane separator and the permeate side of the third membrane separator, such a process may occur. As an illustrative example, Figure 3G The embodiment shown in shows at least a portion of the second membrane separator permeate outlet stream 115 and at least a portion of the third membrane separator permeate outlet stream 144 being conveyed back to the first membrane separator retentate inlet stream 105. At least a portion of the second membrane separator permeate outlet stream 115 and at least a portion of the third membrane separator permeate outlet stream 144 can be conveyed back to the first membrane separator retentate inlet stream 105 by combining to form stream 152. Fig.14D and 15C Similarly shown are at least a portion of the second membrane separator permeate outlet stream 115 and at least a portion of the third membrane separator permeate outlet stream 144 being conveyed back to the first membrane separator retentate inlet stream 105 by combining to form stream 152. The second membrane separator permeate outlet stream 115 and the third membrane separator permeate outlet stream 144 can be combined with the feed stream 104 to form at least a portion of the first membrane separator retentate inlet stream 105.

[0110] In some embodiments, the first membrane separator retentate inlet stream comprises at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%) of the feed stream (e.g., feed stream 101), and at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%) of the upstream membrane separator retentate outlet stream. The term "upstream" in "upstream membrane separator" is used for convenience and refers to the flow direction of the liquid relative to the retentate side of the first membrane separator. The upstream membrane separator may have a retentate side and a permeate side defined by at least one semipermeable membrane. In some such embodiments, the retentate side of the upstream separator receives an upstream membrane separator retentate inlet flow (e.g., by fluidly connecting the retentate side of the upstream membrane separator to one or more other components of the system, such as a retentate side and / or a permeate side of a different membrane separator).

[0111] Reference Figures 3H to 3K , the system 100 may also include an upstream membrane separator 146. The upstream membrane separator 146 may include at least one semipermeable membrane defining a retentate side 147 and a permeate side 148, and an upstream membrane separator retentate inlet stream 149 may be delivered to the retentate side 147 so that an upstream membrane separator retentate outlet stream 150 leaves the retentate side 147. According to some embodiments, this step may be performed so that the osmotic pressure and / or the concentration of dissolved lithium cations of the upstream membrane separator retentate outlet stream 150 is greater than the osmotic pressure and / or the concentration of dissolved lithium cations of the upstream membrane separator retentate inlet stream 149. At least a portion of the upstream membrane separator retentate outlet stream 150 may be combined with at least a portion of the feed stream 104 to form part or all of the first membrane separator retentate inlet stream 105, which is delivered to the retentate side 102 of the first membrane separator 101. Liquid transferred from the retentate side of the upstream membrane separator to the permeate side may form an upstream membrane separator permeate outlet stream (e.g., Figures 3H to 3K The upstream membrane separator in the permeate outlet stream 151) may be discharged from the system (eg, as a relatively pure liquid, such as relatively pure water).

[0112] The upstream separator retentate inlet stream may include at least a portion of one or more streams mentioned elsewhere in this disclosure. For example, in some embodiments, the upstream membrane separator retentate inlet stream includes at least a portion of the first membrane separator permeate outlet stream (e.g., Fig. 3I ), at least a portion of the second membrane separator permeate outlet stream (e.g., Figure 3J), and / or at least a portion of the third membrane separator permeate outlet stream (e.g., as shown in Figure 3K ). These configurations can be achieved, for example, by fluidly connecting the retentate side of the upstream membrane separator to the permeate side of the first membrane separator, the permeate side of the second membrane separator, and / or the permeate side of the third membrane separator.

[0113] In some embodiments, the upstream membrane separator and / or at least one semipermeable membrane of the upstream membrane separator is different from the first membrane separator and / or at least one semipermeable membrane of the first membrane separator in one or more parameters discussed elsewhere in the present disclosure. For example, compared with the first membrane separator, the upstream membrane separator can have different (e.g., lower) salt permeability (salt passage) percentage under standard conditions, different (e.g., lower) solute permeability, different (e.g., higher) solute retention rate, and / or different total membrane surface area. In some embodiments, compared with at least one semipermeable membrane of the first membrane separator, at least one semipermeable membrane of the upstream membrane separator has different (e.g., lower) average molecular weight cutoff (molecular weight cutoff, MWCO).

[0114] In some embodiments, the first membrane separator retentate inlet stream does not include any portion of the upstream membrane separator retentate outlet stream, or less than 10 weight percent, less than 5 weight percent, less than 2 weight percent, less than 1 weight percent, less than 0.1 weight percent, or less of the first membrane separator inlet stream is generated by the upstream membrane separator retentate outlet stream.

[0115] As mentioned above, some methods for obtaining lithium (e.g., as a lithium salt) include removing at least some (e.g., at least 5 weight percent, at least 10 weight percent, at least 20 weight percent, at least 50 weight percent, at least 80 weight percent, at least 90 weight percent, at least 95 weight percent, at least 99 weight percent, or more) of the dissolved non-lithium ions (e.g., sodium cations, potassium cations, magnesium cations, calcium cations) from a concentrate stream to form a decontaminated concentrate stream. Such a process can be advantageous in lithium recovery processes because it can produce a stream having a relatively high concentration of lithium cations compared to the concentration of non-lithium cations, which can be considered impurities in applications where lithium (e.g., lithium salts) is desired in a substantially pure form. In the context of the present disclosure, any material that is not lithium and does not contain lithium is considered an impurity. For example, lithium cations and lithium salts are not considered impurities, but all other non-solvent components are considered impurities. Reference Figures 1A to 3K , 6A to 6B, and 13A to 15C, some methods may include removing (e.g., via one or more ion removal processes not shown) at least some of the dissolved non-lithium cations in the concentrate stream 108 to form the decontaminated concentrate stream 124.

[0116] In some embodiments, the decontaminated concentrate stream has a lower concentration of dissolved non-lithium cations than the concentrate stream. For example, in some embodiments, the ratio of the concentration of non-lithium cations (e.g., sodium cations, potassium cations, magnesium cations, or calcium cations) in the concentrate stream to the concentration of the non-lithium cations in the decontaminated concentrate stream is greater than or equal to 1.1, greater than or equal to 1.2, greater than or equal to 1.5, greater than or equal to 2, greater than or equal to 5, greater than or equal to 10, greater than or equal to 20, greater than or equal to 50, greater than or equal to 100, and / or up to 200, up to 500, up to 1,000, or more. In some embodiments, the ratio of the total concentration of all non-lithium cations in the concentrate stream (e.g., the sum of the concentrations of sodium cations, potassium cations, magnesium cations, calcium cations) to the total concentration of all non-lithium cations in the decontaminated concentrate stream is greater than or equal to 1.1, greater than or equal to 1.2, greater than or equal to 1.5, greater than or equal to 2, greater than or equal to 5, greater than or equal to 10, greater than or equal to 20, greater than or equal to 50, greater than or equal to 100, and / or up to 200, up to 500, up to 1,000, or more.

[0117] In some embodiments where at least some of the dissolved non-lithium cations are removed from the concentrated stream to form a decontaminated concentrated stream, both the absolute concentration of non-lithium cations and the absolute concentration of lithium cations are increased relative to the concentrated stream, but the absolute concentration of lithium ions is increased to a greater extent than the absolute concentration of non-lithium cations. Therefore, the use of the term "decontaminated concentrated stream" does not necessarily mean that the absolute concentration of non-lithium cations in the liquid is reduced. For example, precipitation induced by concentration may occur despite the removal of at least some of the non-lithium cations, but such an increase in the concentration of non-lithium cations. For example, non-lithium cations may be dissolved in a concentrated stream having a concentration lower than the saturation point of these non-lithium cations. During the removal process, such a concentrated stream may be subjected to a liquid removal process and / or a heating process (e.g., via boiling) so that the non-lithium cations are concentrated to the saturation point. Under saturation, a salt precipitate containing at least some non-lithium cations may be formed and separated from the stream, thereby removing at least some of the non-lithium cations from the stream, while the concentration of the non-lithium cations is maintained at the saturation point. At the same time, lithium cations may also be dissolved in a concentrated stream having a concentration lower than the saturation point of the lithium cations. During the same removal process in which the concentrate stream is subjected to the liquid removal process to form the decontaminated concentrate stream, the lithium cations are also concentrated, but to a greater extent than the non-lithium cations because, under the operating conditions, the saturation point of the lithium cations is higher than that of the non-lithium cations. Thus, as at least some of the non-lithium cations are removed via precipitation, the lithium cations can continue to be concentrated while the concentration of the non-lithium cations reaches and remains at its saturation point.

[0118] In some embodiments, the process of removing at least some of the dissolved non-lithium cations from the concentrate stream forms a decontaminated concentrate stream having an atomic ratio of lithium cations to non-lithium cations greater than the atomic ratio of lithium cations to non-lithium cations in the concentrate stream. In some embodiments, during the process of removing at least some of the dissolved non-lithium cations from the concentrate stream, the amount of dissolved non-lithium cations removed is greater than the amount of any dissolved lithium cations removed (which may be zero or non-zero amount). Such selective removal of non-lithium cations relative to lithium cations can produce a lithium-enriched stream that is useful for obtaining relatively pure lithium-containing products (e.g., lithium salts). In some embodiments, dissolved lithium cations are barely removed during such a process, while in some embodiments, the concentration of dissolved lithium cations increases (e.g., due to a reduction in liquid volume). In some embodiments, the ratio of the concentration of dissolved lithium cations in the concentrate stream to the concentration of dissolved lithium cations in the decontaminated concentrate stream is less than or equal to 1.05, less than or equal to 1.02, less than or equal to 1, less than or equal to 0.9, less than or equal to 0.8, less than or equal to 0.5, less than or equal to 0.2, less than or equal to 0.1, and / or as low as 0.01, or less. In some embodiments, the ratio of the total concentration of all dissolved non-lithium cations (e.g., sodium cations, potassium cations, magnesium cations, or calcium cations) in the concentrate stream to the total concentration of all dissolved non-lithium cations in the decontaminated concentrate stream is greater than or equal to 1.1, greater than or equal to 1.2, greater than or equal to 1.5, greater than or equal to 2, greater than or equal to 5, greater than or equal to 10, greater than or equal to 20, greater than or equal to 50, greater than or equal to 100, and / or up to 200, up to 500, up to 1,000, or more, and the ratio of the concentration of dissolved lithium cations in the concentrate stream to the concentration of dissolved lithium cations in the decontaminated concentrate stream is less than or equal to 1.05, less than or equal to 1.02, less than or equal to 1, less than or equal to 0.9, less than or equal to 0.8, less than or equal to 0.5, less than or equal to 0.2, less than or equal to 0.1, and / or as low as 0.01, or less. In some embodiments, the process of removing at least some of the dissolved non-lithium cations from the concentrate stream results in a ratio of the concentration of dissolved lithium cations to the total concentration of all dissolved non-lithium cations in the decontaminated concentrate stream that is at least 1.1 times, at least 1.2 times, at least 1.5 times, at least 2 times, at least 5 times, at least 10 times, at least 20 times, at least 50 times, at least 100 times, at least 200 times, at least 500 times, and / or up to 1,000 times, up to 10,000 times, or more greater than the ratio of the concentration of dissolved lithium cations to the total concentration of all dissolved non-lithium cations in the concentrate stream. As will be readily appreciated, these ranges may also be expressed in terms of atomic ratios rather than concentration ratios.For example, in addition to or instead of satisfying the above concentration ratios on a mass basis, in some embodiments, the process of removing at least some of the dissolved non-lithium cations from the concentrate stream results in an atomic ratio of dissolved lithium cations to total dissolved non-lithium cations in the decontaminated concentrate stream that is at least 1.1 times, at least 1.2 times, at least 1.5 times, at least 2 times, at least 5 times, at least 10 times, at least 20 times, at least 50 times, at least 100 times, at least 200 times, at least 500 times, and / or up to 1,000 times, up to 10,000 times, or more greater than the atomic ratio of dissolved lithium cations to total dissolved non-lithium cations in the concentrate stream.

[0119] Any of a variety of suitable techniques may be used to remove dissolved non-lithium cations from the concentrate stream to a greater extent than the removal of dissolved lithium cations. In some embodiments, during the generation of the decontaminated concentrate stream, at least a portion of the non-lithium cations removed from the concentrate stream (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt% or more) is removed as a solid non-lithium salt containing at least a portion of the non-lithium cations. Other techniques that can be used to remove non-lithium cations include, but are not limited to, extraction (e.g., liquid-liquid extraction, solvent extraction, extraction with compounds and / or solvents having a preferential affinity for non-lithium cations) and membrane-based techniques (e.g., dialysis, electrodialysis, nanofiltration). In some cases where it is desired that non-lithium and lithium-containing materials are easily separated, and in some cases where the concentration of non-lithium ions is relatively high (e.g., in some embodiments, after the above-mentioned liquid removal step), it may be advantageous to remove non-lithium cations as solid non-lithium salts. In some cases, it may be convenient to remove the solid non-lithium-containing salt because doing so may require only collecting the mother liquor / supernatant liquor after the solid non-lithium-containing salt has been removed.

[0120] Any of a variety of non-lithium-containing salts may be formed from one or more solutions (e.g., streams) described in the present disclosure, depending on the composition of the solution. In some embodiments, the non-lithium-containing salt comprises cations selected from one or more of sodium and potassium, and anions selected from one or more of chloride, sulfate, carbonate, bicarbonate, nitrate, borate, phosphate, bromide, citrate, oxygen anions, and hydrogen anions. For example, in some embodiments where the concentrate stream comprises dissolved sodium and potassium cations and dissolved chloride anions, an amount of solid sodium chloride and / or potassium chloride may be removed from the concentrate stream during generation of the decontaminated concentrate stream.

[0121] In some embodiments, at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the solid non-lithium-containing salt is formed via precipitation from a concentrate stream (or a stream comprising at least a portion of the concentrate stream). In some embodiments, the solid non-lithium-containing salt is formed via crystallization from a concentrate stream (or a stream comprising at least a portion of the concentrate stream). Precipitation and / or crystallization of the non-lithium-containing salt can occur in a non-lithium-containing salt production unit. For example, in Figure 4A In the embodiment shown in , at least a portion of the concentrated stream 108 can be fed to a non-lithium-containing salt production unit 125, in which a certain amount of non-lithium-containing salt containing at least a portion of non-lithium cations is formed, thereby forming a decontaminated concentrated stream 124. The non-lithium-containing salt production unit may include one or more containers for receiving at least a portion of the liquid stream (e.g., via a liquid inlet). In some embodiments, the non-lithium-containing salt production unit includes a heater thermally connected to the container (e.g., for increasing the temperature of the liquid in the container). In some embodiments, the non-lithium-containing salt production unit includes a cooling device thermally connected to the container (e.g., for reducing the temperature of the liquid in the container). In some embodiments, the non-lithium-containing salt production unit includes a precipitation unit configured to induce precipitation and / or crystallization. Examples of equipment suitable for non-lithium-containing salt production (e.g., via precipitation) include, but are not limited to, forced circulation evaporators, solvent extraction equipment, flotation devices, electrodialysis devices, and low-temperature eutectic freeze crystallization equipment. In some embodiments, the non-lithium-containing salt production unit includes a cooling unit (e.g., a cooler) fluidly connected to the precipitation device. For example, in Figure 4A In the embodiment, the non-lithium-containing salt production unit 125 includes a precipitation unit 126 fluidly connected to a cooling unit 127.

[0122] One process for inducing precipitation of non-lithium-containing salts is to remove the non-lithium-containing salts from a solution containing lithium cations and non-lithium cations via chemical treatment. Due to the different solubilities of lithium salts and non-lithium-containing salts under certain conditions, such chemical treatments can result in selective precipitation of non-lithium-containing salts relative to lithium salts. One such example is the addition of aluminum sulfate to a solution containing dissolved lithium cations and non-lithium cations (e.g., alkali metals or alkaline earth metals). Adding aluminum sulfate can result in precipitation of non-lithium-containing sulfates (e.g., alunite and / or alum) to a greater extent than any lithium-containing sulfates.

[0123] A different method of selectively precipitating non-lithium containing salts is to change the temperature of the liquid containing dissolved lithium cations and non-lithium cations. Such a process can be carried out without chemical treatment of the concentrate stream. The solubility of lithium salts and non-lithium containing salts is generally temperature dependent. However, the solubility of at least some lithium salts can be greater than the solubility of at least some non-lithium containing salts and vary with temperature to a greater extent than at least some non-lithium containing salts. For example, the solubility of lithium chloride (LiCl) in water increases from about 80 g / 100 g water to about 140 g / 100 g water from 20°C to 140°C - an increase of about 75% in solubility. However, the solubility of potassium chloride (KCl) in water increases only from about 39 g / 100 g water to about 65 g / 100 g water from 20°C to 140°C - an increase of only 67% from a lower absolute value compared to the solubility of lithium chloride in water. Even more significantly, the solubility of sodium chloride (NaCl) in water increases only from about 39 g / 100 g water to about 42 g / 100 g water - an increase of only about 8% from a lower absolute value compared to the solubility of lithium chloride in water. Thus, raising the temperature of an aqueous solution comprising lithium cations, potassium cations, sodium cations, and chloride anions to a sufficiently high temperature (e.g., by boiling and / or evaporating at least some of the aqueous solution) can cause potassium chloride and sodium chloride to precipitate to a greater extent than any precipitation of lithium chloride. As a result, the remaining aqueous solution can be enriched in lithium cations compared to any remaining potassium or sodium cations.

[0124] Thus, in some embodiments, removing at least some of the dissolved non-lithium cations from a concentrate stream (e.g., comprising a liquid such as water, dissolved lithium cations, and dissolved non-lithium cations) comprises increasing the temperature of the concentrate stream to form a heated concentrate stream such that a quantity of solid non-lithium-containing salts comprising at least a portion of the non-lithium cations is formed. In some such embodiments, the temperature of the heated stream is greater than or equal to 100°C, greater than or equal to 110°C, greater than or equal to 120°C, greater than or equal to 140°C, and / or up to 160°C, or higher. In some embodiments, the temperature of the heated concentrate stream is at least 5°C, at least 10°C, at least 20°C, at least 50°C, at least 100°C, at least 120°C, at least 140°C, and / or up to 150°C, or higher, higher than the temperature of the concentrate stream.

[0125] Any of a variety of techniques and suitable equipment may be used to increase the temperature of the concentrate stream so that the non-lithium-containing salt is formed (e.g., via precipitation). In some embodiments, as described above, the temperature increase is performed in a precipitation unit of the non-lithium-containing salt production unit (e.g., in Figure 4BThe heated concentrated stream 128 can be produced by the precipitation unit 126 of the non-lithium-containing salt production unit 125). In some embodiments, the precipitation unit is a container configured to heat a liquid (e.g., by being equipped with a heater that is thermally connected to the container). In some embodiments, the precipitation unit is configured to boil and / or evaporate the liquid (e.g., water) of the concentrated stream. In some embodiments, the concentrated stream boils at atmospheric pressure (e.g., 90 kPa to 110 kPa) while causing the concentrated stream to circulate. An example of an apparatus suitable for doing this is a forced circulation evaporator. Non-lithium-containing salts (e.g., NaCl, KCl) can be formed (e.g., precipitated) in a forced circulation evaporator.

[0126] In some embodiments, part (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) or all of the non-lithium-containing salts formed during the temperature increase of the concentrate stream are separated from the heated concentrate stream. Such separation of solids from the heated concentrate stream can be performed using any suitable technique known in the art (e.g., filtration, centrifugation, decantation, etc.).

[0127] In some embodiments, the method of obtaining lithium (e.g., as a lithium salt) is performed so that at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the heated concentrate stream is part of the decontaminated concentrate stream. The incorporation of the heated concentrate stream into the decontaminated concentrate stream can be direct or indirect.

[0128] In some embodiments, the process of removing at least some of the dissolved non-lithium cations from the concentrate stream includes reducing the temperature of the heated concentrate stream so that an additional amount of solid non-lithium-containing salt is formed. Such a reduction in temperature can reduce the solubility of salts that may be formed from dissolved lithium cations and non-lithium cations. It is believed that the solubility difference and temperature dependence of at least some lithium-containing salts and non-lithium-containing salts can result in a greater degree of formation of solid non-lithium-containing salts than the degree of formation of lithium-containing salts during the temperature reduction. In some embodiments, the temperature of the heated concentrate stream is reduced to a temperature less than or equal to 40°C, less than or equal to 35°C, and / or as low as 30°C, or lower.

[0129] Any of a variety of techniques and suitable equipment may be used to reduce the temperature of the heated concentrate stream so that additional amounts of non-lithium-containing salts are formed (e.g., via precipitation). In some embodiments, the temperature reduction is performed in a cooling unit (e.g., Figure 4BIn some embodiments, the cooling unit is a container configured to cool (e.g., by being provided with a heat exchanger or refrigeration device in thermal communication with the container) a liquid. An example of a suitable device for reducing the temperature of a heated concentrated stream (e.g., containing water) is a cooler. Non-lithium-containing salts (e.g., NaCl, KCl) can be formed (e.g., precipitated) in a cooler.

[0130] In some embodiments, part (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) or all of the non-lithium-containing salts formed during the temperature reduction of the heated concentrated stream are separated from the resulting solution (e.g., stream). Such separation of solids from the resulting solution can be performed using any suitable technique known in the art (e.g., filtration, centrifugation, decantation, etc.).

[0131] In some embodiments, the method of obtaining lithium (e.g., as a lithium salt) is performed so that at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the solution produced by reducing the temperature of the heated concentrated stream is part of the decontaminated concentrated stream. The incorporation of the resulting liquid from reducing the temperature of the heated concentrated stream can be direct (e.g., as produced by Figure 4B as shown in the decontaminated concentrated flow leaving cooling unit 127) or indirectly.

[0132] In some embodiments, the method for obtaining lithium (e.g., as a lithium salt) from a liquid involves treating the solution via an electrochemical process. Such an electrochemical process can promote that the counterions of dissolved lithium ions are at least partially replaced by different counterions. It is recognized that for at least some commercial / industrial applications, lithium salts with specific counterions are generally more desirable or more useful than lithium salts with counterions that may be more common in a feed stream. For example, in some cases, solid lithium hydroxide (LiOH) is a desired product, and the available lithium ion source (e.g., salt lake brine) or its processed product is relatively rich in dissolved chloride anions, but relatively poor in dissolved hydroxide ions. In some such cases, it is desirable to replace part or all of the chloride anions with hydroxide anions. In the context of the present disclosure, it is recognized that certain electrochemical processes can be very suitable (e.g., in terms of energy consumption and ease of integration into a lithium recovery system) for some such lithium counterion replacements.

[0133] In some embodiments, the lithium recovery system includes an electrochemical cell. Figure 5AA schematic cross-sectional view of an electrochemical cell 129 according to some embodiments is shown. An electrochemical cell generally refers to a device that can use electrical energy to initiate a chemical reaction and / or use a chemical reaction to generate electrical energy. Examples of types of electrochemical cells include electrolytic cells and galvanic cells. In some embodiments, an electrochemical cell (e.g., electrochemical cell 129) is an electrolytic cell that can drive a reduction-oxidation chemical reaction via an applied voltage. In some embodiments, an electrochemical cell is a galvanic cell in which a thermodynamically spontaneous reduction-oxidation reaction is performed while generating an electric current across electrodes.

[0134] In some embodiments, the initial solution (e.g., liquid solution) is associated with an electrochemical cell. For example, in some embodiments, the electrochemical cell includes a first electrode and a second electrode, and at least a portion of the initial solution is in contact with at least a portion of the first electrode and / or the second electrode. For example, Figure 5A The embodiment shown in FIG. 1 has an initial solution 130 between a first electrode 131 and a second electrode 132 of an electrochemical cell 129 .

[0135] The initial solution may include a liquid, dissolved lithium cations, and dissolved first anions. Figure 5A The initial solution 130 contains dissolved lithium ions Li + and dissolved first anion A - . The liquid can be water or include water. For example, in some embodiments, at least 10% by weight, at least 25% by weight, at least 50% by weight, at least 75% by weight, at least 90% by weight, at least 95% by weight, at least 98% by weight, at least 99% by weight, at least 99.9% by weight, or more of the liquid is water. The first anion can be selected from one or more of chloride, sulfate, carbonate, bicarbonate, nitrate, borate, phosphate, bromide, citrate, oxygen anion, and hydrogen anion.

[0136] Some embodiments include applying a voltage to an electrochemical cell comprising an initial solution. In some such embodiments, the voltage is applied such that at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the first anion is replaced by a different second anion, thereby forming an electrochemically treated solution comprising a liquid, dissolved lithium cations, and dissolved second anions. For example, with reference to FIG. 5A to FIG. 5B , the electrochemical cell 129 may initially contain an initial solution 130 ( Figure 5A ), and after applying a sufficient voltage V across the first electrode 131 and the second electrode 132 ( Figure 5B ), the first anion A - At least some of the -substituted, thereby forming an electrochemically treated solution 133. Depending on the desired application, the second anion (e.g., Figure 5B The second anion X - ) can be any of a variety of different types of anions (e.g., hydroxides, halides, oxygen anions). The second anion may be able to form a lithium salt having more desirable properties than a lithium salt comprising the first anion. For example, a lithium salt comprising the second anion may have a different solubility than a lithium salt comprising the first anion, which can be useful in downstream purification processes. In some cases, a lithium salt comprising the second anion is more commercially valuable than a lithium salt comprising the first lithium salt. For example, lithium hydroxide may be more commercially valuable than lithium chloride (e.g., for lithium ion battery applications), and therefore replacing at least a portion of the chloride ions in the solution with hydroxide ions may be beneficial for some applications. In some embodiments, the second anion is more electronegative than the first anion. As Figure 5C As shown in FIG. 1 , at least a portion of the electrochemically treated solution can be transferred from the electrochemical cell (eg, electrochemical cell 129 ) for further processing, such as further concentration (eg, in a humidifier such as second humidifier 134 ), as described in more detail below.

[0137] In some embodiments, the electrochemically treated solution contains dissolved second anions at a concentration greater than the concentration of dissolved second anions in the initial solution. For example, in some embodiments, the ratio of the concentration of dissolved second anions in the electrochemically treated solution to the concentration of dissolved second anions in the initial solution is greater than or equal to 1.1, greater than or equal to 1.2, greater than or equal to 1.5, greater than or equal to 2, greater than or equal to 5, greater than or equal to 10, greater than or equal to 100, greater than or equal to 1,000, greater than or equal to 10,000, greater than or equal to 100,000, and / or up to 1,000,000, or greater. After the voltage is applied, the concentration of dissolved lithium cations can be relatively unchanged. For example, in some embodiments, the ratio of the concentration of dissolved lithium cations in the initial solution to the concentration of dissolved lithium cations in the electrochemically treated solution is less than or equal to 1.2, less than or equal to 1.1, less than or equal to 1.05, less than or equal to 1.02, less than or equal to 1, and / or as low as 0.98, as low as 0.95, as low as 0.9, or as low as 0.8.

[0138] As an illustrative example of an embodiment in which the electrochemical cell is an electrolytic cell, the initial solution can be an initial aqueous solution (e.g., from a salt water) comprising dissolved lithium cations and dissolved chloride anions. A voltage can be applied to drive an electrolysis reaction in which (a) the lithium ions are reduced at the first electrode to form Li 0 (e.g., lithium metal), which can react rapidly with water to produce hydrogen gas (H 2), hydroxide anion (OH - ) and lithium cation (Li + ); and (b) the chloride ions are oxidized to form chlorine gas (Cl 2 ) products. Hydrogen and chlorine can be removed from the resulting electrochemically treated solution (e.g., via bubbling), leaving lithium cations and hydroxide anions in solution (thereby achieving at least partial replacement of chloride anions with hydroxide anions).

[0139] In some embodiments, the initial solution in the electrochemical cell (e.g., Figure 5A The initial solution 130 in the reactor (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) contains at least a portion of the above-described decontaminated concentrated stream (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more). Such a process can promote mild anion exchange to produce a desired lithium salt derived from a feed stream (e.g., salt lake brine or extract from spent lithium-ion batteries). As an example, Figures 6A to 6B An example of an embodiment of a lithium recovery system 100 is shown in which at least a portion of a decontaminated concentrate stream 124 is delivered from a non-lithium containing salt production unit 125 to an electrochemical cell 129, wherein application of a voltage may cause at least some of the anions (chloride ions) of the decontaminated concentrate stream 124 to be replaced with different anions (e.g., hydroxide ions), followed by further downstream processing as described in more detail below. Fig. 6A In the embodiment shown in FIG. 1 , the decontaminated concentrate stream 124 may be produced by removing liquid from the feed stream 104 via the first membrane separator 101 and the humidifier 117 prior to removing at least a portion of the dissolved non-lithium cations in the non-lithium salt production unit 125. Figure 6B In the embodiment shown in , before removing at least a portion of the dissolved non-lithium cations in the non-lithium-containing salt production unit 125, a decontaminated concentrated stream 124 can be produced by removing liquid from the feed stream 104 via a first membrane separator 101, a second membrane separator 110, and a humidifier 117.

[0140] In some embodiments, liquid is removed from an electrochemically treated solution (e.g., containing liquid, dissolved lithium cations and second anions) produced by an electrochemical cell. In some cases where a relatively concentrated stream of lithium cations and second anions is desired (e.g., for obtaining solid salts of lithium cations and second anions), such liquid removal may be useful. In some embodiments, at least a portion of the liquid from the electrochemically treated solution is evaporated in a humidifier to produce a humidified gas stream and a humidifier liquid outlet stream. In some embodiments, the humidifier is the same humidifier as described above with respect to removing liquid from a feed stream. However, in other embodiments, more than one humidifier (which may be of the same or different types) may be used.

[0141] As an example, in Figure 5C and Figures 6A to 6B In the embodiment of the present invention, the second humidifier 134 receives a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) or all of the liquid output of the electrochemical cell 129 via a second humidifier liquid inlet stream 135. At least a portion of the liquid of the second humidifier liquid inlet stream 135 can be evaporated by the second humidifier 134 to produce a second humidified gas stream 136 (including at least a portion of the vapor produced by evaporation) and a second humidifier liquid outlet stream 137. In some cases, part or all of the second humidified gas stream is delivered to a dehumidifier, where the liquid in the second humidified gas stream can be condensed to form a liquid stream (e.g., including substantially pure water).

[0142] In some embodiments, the humidifier liquid outlet stream (e.g., the second humidifier liquid outlet stream 137) has a higher concentration of dissolved lithium cations and dissolved second anions than the electrochemically treated solution delivered to the humidifier. For example, the ratio of the concentration of dissolved lithium cations in the humidifier liquid outlet stream to the concentration of dissolved lithium cations in the electrochemically treated solution can be greater than or equal to 1.1, greater than or equal to 1.2, greater than or equal to 1.5, greater than or equal to 2, greater than or equal to 5, greater than or equal to 10, greater than or equal to 20, greater than or equal to 25, greater than or equal to 50, and / or up to 100 or more.

[0143] In some embodiments, a solid lithium salt comprising at least a portion of the lithium cations derived from a feed stream (e.g., from a decontaminated concentrate stream, from an electrochemically treated solution, and / or from a humidifier liquid outlet stream) is obtained. For example, in some embodiments, a solid lithium salt comprising at least a portion of the lithium cations from the humidifier liquid outlet stream (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) and at least a portion of the second anions (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) is obtained. As an example, in some embodiments, the humidifier liquid outlet stream of a humidifier fed with a partial or full electrochemically treated solution comprises dissolved lithium cations and dissolved hydroxide ions. Some embodiments relate to obtaining solid lithium hydroxide (LiOH) from the humidifier liquid outlet stream. Reference Figures 6A to 6B , the solid lithium salt forming unit 138 can receive part or all of the second humidifier liquid outlet stream 137. The solid lithium salt forming unit 138 can be any of a variety of devices capable of inducing the formation of a solid lithium salt from a solution. For example, obtaining a solid lithium salt can include removing a liquid from the second humidifier liquid outlet stream, in some cases via heating (e.g., via boiling / evaporation). In some embodiments, the formation of a solid lithium salt includes a forced circulation evaporator. In some embodiments, a solid lithium salt (e.g., LiOH) is obtained via crystallization. In some cases, a solid lithium salt is obtained by (e.g., by applying a vacuum) under reduced pressure conditions (optionally while heating). It is known that obtaining solid salts of some lithium-containing compounds such as lithium hydroxide is challenging, at least because some such salts are relatively hygroscopic. In the context of the present disclosure, it has been recognized that a relatively concentrated solution of dissolved cations and anions that form such a salt can help to obtain a solid salt. In some cases, using a humidifier to produce such a high concentration solution can be advantageous, at least because a humidifier can produce a sufficiently high dissolved lithium cation concentration with relatively low energy input and / or relatively quickly compared to typical techniques such as solar evaporation.

[0144] In some embodiments, the obtained solid lithium salt can be further processed and / or packaged for commercial and / or industrial purposes. For example, the lithium salt product can be obtained by filling and loading a container with the solid lithium salt. Pneumatic conveying followed by sealing using a commercially available form-fill-seal system is one way to package the solid lithium salt.

[0145] In some embodiments, the pressure of any one of the streams described herein can be increased via one or more other components, such as one or more booster pumps. In some embodiments, the pressure of any one of the streams described herein can be reduced via one or more other components, such as one or more other valves or energy recovery devices. In some embodiments, the membrane separator described herein also includes one or more heating, cooling or other concentration or dilution mechanisms or devices.

[0146] The membrane separators described herein (eg, the first membrane separator, the second membrane separator, the third membrane separator) may each include a single semipermeable membrane or a plurality of semipermeable membranes.

[0147] Fig. 7A 200A is a schematic diagram of a membrane separator 200A, in which a single semipermeable membrane is used to separate a permeate side 204 from a retentate side 206. The membrane separator 200A can be operated by conveying a retentate inlet stream 210 through the retentate side 206. The liquid (e.g., solvent) in the retentate inlet stream 210 and at least a portion of the solute in some cases can be conveyed through the semipermeable membrane 202 to the permeate side 204. This can result in the formation of a retentate outlet stream 212 and a permeate outlet stream 214, the retentate outlet stream 212 can contain a concentration of solutes higher than the concentration of the solutes contained in the retentate inlet stream 210. The permeate outlet stream 214 can correspond to the liquid (e.g., solvent) and in some cases the solute of the retentate inlet stream 210 conveyed from the retentate side 206 to the permeate side 204.

[0148] In some embodiments, the membrane separator (e.g., the first membrane separator, the second membrane separator, the third membrane separator) includes a plurality of semipermeable membranes connected in parallel. An example of such an arrangement is shown in Figure 7B In. Figure 7BIn, membrane separator 200B comprises three semipermeable membranes 202A, 202B and 202C arranged in parallel.Retentate inlet stream 210 is divided into three substreams, one of which is fed to the retentate side 206A of semipermeable membrane 202A, another substream is fed to the retentate side 206B of semipermeable membrane 202B, and another substream is fed to the retentate side 206C of semipermeable membrane 202C.Membrane separator 200B can be operated by transporting the retentate inlet substream through the retentate side of semipermeable membrane.Liquid (for example, solvent) in retentate inlet stream 210 and at least a portion of solute in some cases can be transported through each of semipermeable membrane 202A, 202B and 202C to permeate side 204A, 204B and 204C respectively. This can result in the formation of three retentate outlet substreams, which can be combined to form the retentate outlet stream 212. The retentate outlet stream 212 can contain solutes at a higher concentration than the solutes contained in the retentate inlet stream 210. A permeate outlet stream 214 can also be formed (from the three permeate outlet substreams). The permeate outlet stream 214 can correspond to the liquid (e.g., solvent) and, in some cases, solutes, delivered from the retentate side 206A to 206C to the retentate inlet stream 210 of the permeate side 204A to 204C.

[0149] Although Figure 7B Three semipermeable membranes connected in parallel are shown, but other embodiments may include 2, 4, 5 or more semipermeable membranes connected in parallel.

[0150] In some embodiments, the membrane separator (e.g., first membrane separator, second membrane separator) comprises a plurality of semipermeable membranes connected in series. An example of such an arrangement is shown in Figure 7C In. Figure 7C In the embodiment, the membrane separator 200C includes three semi-permeable membranes 202A, 202B and 202C arranged in series. Figure 7CIn the embodiment of the present invention, the retentate inlet stream 210 is first delivered to the retentate side 206A of the semipermeable membrane 202A. The liquid (e.g., solvent) in the retentate inlet stream 210 and at least a portion of the solute in some cases can be transported through the semipermeable membrane 202A to the permeate side 204A of the semipermeable membrane 202A. This can result in the formation of a permeate outlet stream 214 and a first intermediate retentate stream 240 that is transported to the retentate side 206B of the semipermeable membrane 202B. The liquid (e.g., solvent) in the first intermediate retentate stream 240 and at least a portion of the solute in some cases can be transported through the semipermeable membrane 202B to the permeate side 204B of the semipermeable membrane 202B. This can result in the formation of a permeate outlet stream 250 and a second intermediate retentate stream 241 that is transported to the retentate side 206C of the semipermeable membrane 202C. At least a portion of the liquid (eg, solvent) and in some cases the solutes within the second intermediate retentate stream 241 may be transported across the semipermeable membrane 202C to the permeate side 204C of the semipermeable membrane 202C. This may result in the formation of a permeate outlet stream 251 and a retentate outlet stream 212.

[0151] Although Figure 7C Three semipermeable membranes connected in series are shown, but other embodiments may include 2, 4, 5 or more semipermeable membranes connected in series.

[0152] For a membrane separator comprising a plurality of semipermeable membranes, parameters of the membrane separator such as percent rejection, percent recovery and percent salt permeability under standard conditions are calculated by performing a mass balance on the entire membrane separator. This means that all initial retentate flows of the membrane separator will be added and considered together, all final permeate outlet flows of the membrane separator will be added and considered together, and all final retentate outlet flows of the membrane separator will be added and considered together. For example, as mentioned above, in Figure 7B, membrane separator 200B includes three semipermeable membranes 202A, 202B, and 202C arranged in parallel. Therefore, calculating the composition of the retentate inlet stream of membrane separator 200B for the purpose of calculating parameters such as percent rejection, percent recovery, and percent salt pass-through of membrane separator 200B under standard conditions will involve measuring the retentate inlet stream 210 before it is divided into three inlet substreams fed to the retentate sides 206A, 206B, and 206C of the semipermeable membranes 202A, 202B, and 202C, respectively. Similarly, calculating the composition of the retentate outlet stream of membrane separator 200B for the purpose of calculating parameters such as percent rejection, percent recovery, and percent salt pass-through of membrane separator 200B under standard conditions will involve measuring retentate outlet stream 212, which is a combination of three outlet substreams from the retentate sides 206A, 206B, and 206C of semipermeable membranes 202A, 202B, and 202C, respectively. Also similarly, calculating the composition of the permeate outlet stream of membrane separator 200B for the purpose of calculating parameters such as percent rejection, percent recovery, and percent salt pass-through under standard conditions will involve measuring permeate outlet stream 214, which is a combination of three outlet substreams from the permeate sides 204A, 204B, and 204C of semipermeable membranes 202A, 202B, and 202C, respectively.

[0153] As another example of calculating the parameters corresponding to the membrane separator including a plurality of semipermeable membranes, refer to Figure 7CThe membrane separator 200C in the embodiment of the present invention comprises three semipermeable membranes 202A, 202B and 202C arranged in series. Therefore, for the purpose of calculating parameters such as the rejection percentage, recovery rate and salt permeability percentage of the membrane separator 200C under standard conditions, calculating the composition of the retentate inlet stream of the membrane separator 200C will involve measuring the retentate inlet stream 210 before it enters the semipermeable membrane 202A, because the semipermeable membrane 202A is the initial semipermeable membrane in the series. Similarly, calculating the composition of the retentate outlet stream of membrane separator 200C for the purpose of calculating parameters such as percent rejection, recovery, and percent salt penetration of membrane separator 200C under standard conditions will involve measuring the retentate outlet stream 212 leaving semipermeable membrane 202C, because semipermeable membrane 202C is the last semipermeable membrane in the series with respect to the retentate outlet stream, making retentate outlet stream 212 the final retentate outlet stream of membrane separator 200C. Calculating the composition of the permeate outlet stream of membrane separator 200C for the purpose of calculating parameters such as percent rejection, recovery, and percent salt penetration under standard conditions will involve measuring the combination of permeate outlet streams 214, 250, and 251 leaving semipermeable membranes 202A, 202B, and 202C, respectively. In addition, in some embodiments, a given membrane separator may include a plurality of semipermeable membranes connected in parallel as well as a plurality of semipermeable membranes connected in series.

[0154] In some embodiments, the first membrane separator comprises a plurality of semipermeable membranes. In some such embodiments, a plurality of semipermeable membranes in the first membrane separator are connected in series. In some such embodiments, a plurality of semipermeable membranes in the first membrane separator are connected in parallel. In certain embodiments, the first membrane separator comprises a plurality of films, and its first part is connected in series, and its another part is connected in parallel.

[0155] In some embodiments, the second membrane separator comprises a plurality of semipermeable membranes. In some such embodiments, a plurality of semipermeable membranes in the second membrane separator are connected in series. In some such embodiments, a plurality of semipermeable membranes in the second membrane separator are connected in parallel. In certain embodiments, the second membrane separator comprises a plurality of films, and its first part is connected in series, and its another part is connected in parallel.

[0156] In some embodiments, the third membrane separator comprises a plurality of semipermeable membranes. In some such embodiments, a plurality of semipermeable membranes in the third membrane separator are connected in series. In some such embodiments, a plurality of semipermeable membranes in the third membrane separator are connected in parallel. In certain embodiments, the third membrane separator comprises a plurality of films, and its first part is connected in series, and its another part is connected in parallel.

[0157] As mentioned above, each membrane separator of system can include at least one semipermeable membrane.Generally, semipermeable membrane is to allow some components of mixture to pass through, and to block at least some (for example, to block all of another component, or to reduce the relative permeability of another component) barriers of other components.For example, semipermeable membrane can block some molecules in liquid solution to pass through, and allow others to pass through.In some cases, semipermeable membrane blocks some molecules based on the molecular weight and / or charge of molecule and allows other molecules to pass through.As mentioned above, semipermeable membrane can be used for osmotic process.For example, semipermeable membrane can be permeable membrane.Permeable membrane can be able to produce osmotic pressure difference between the solutions on each side of membrane when applying hydraulic pressure difference on both sides of transmembrane.For example, if permeable membrane is placed between two solutions of the same composition, so that there is no osmotic pressure difference across membrane at first, then applying the hydraulic pressure difference across permeable membrane can allow component to be transported to the other side from one side of membrane, so that the osmotic pressure difference on both sides of transmembrane is established.Semipermeable membrane can also be used for nanofiltration process. Semipermeable membranes can be configured for osmosis processes, nanofiltration processes, and / or processes in which separation is achieved based on a combination of nanofiltration and osmosis mechanisms (e.g., based on, for example, the molecular weight cutoff of the membrane, the pore size of the membrane, the nature of the mixture to which they are exposed, and the magnitude of the applied hydraulic pressure).

[0158] Semipermeable membrane media may include, for example, metals, ceramics, polymers (e.g., polyamides, polyethylene, polyesters, poly(tetrafluoroethylene), polysulfones, polycarbonates, polypropylenes, poly(acrylates)), and / or composites or other combinations thereof. Semipermeable membranes typically allow a solvent (e.g., water) to be selectively transported through the membrane, wherein the solvent is able to be transported through the membrane while solutes (e.g., dissolved substances, such as dissolved ions) are inhibited from being transported through the membrane. Examples of commercially available semipermeable membranes that may be used in connection with certain embodiments described herein include, but are not limited to, those commercially available from Dow Water and Process Solutions (e.g., FilmTec TM Membranes), semipermeable membranes from Hydranautics, GE Osmonics, Suez, LG, Toyobo, Microdyn, and Toray Membrane, and other semipermeable membranes known to those of ordinary skill in the art.

[0159] In some embodiments, the average pore size of the semipermeable membrane of the first membrane separator, the second membrane separator and / or the third membrane separator is greater than or equal to 0.0001 micron, greater than or equal to 0.001 micron, greater than or equal to 0.002 micron or larger. In some embodiments, the average pore size of the semipermeable membrane of the first membrane separator, the second membrane separator and / or the third membrane separator is less than or equal to 0.01 micron, less than or equal to 0.005 micron or smaller. The combination of these ranges (for example, greater than or equal to 0.0001 micron and less than or equal to 0.01 micron) is possible.

[0160] In some embodiments, the average pore size of the semipermeable membrane of the second membrane separator is (for example, at least 1.05 times, at least 1.1 times, at least 1.2 times, at least 1.5 times, at least 2 times, at least 3 times, at least 5 times or more times) of the average pore size of the semipermeable membrane of the first membrane separator. In some embodiments, the average pore size of the semipermeable membrane of the third membrane separator is (for example, at least 1.05 times, at least 1.1 times, at least 1.2 times, at least 1.5 times, at least 2 times, at least 3 times, at least 5 times or more times) of the average pore size of the semipermeable membrane of the second membrane separator. The average pore size of the semipermeable membrane can affect any one of the multiple parameters discussed below, such as solute permeability, water permeability, salt permeability, rejection rate, and / or recovery rate. For example, mercury intrusion porosimetry can be used to determine the average pore size.

[0161] In some embodiments, the semipermeable membrane of the membrane separator of the present disclosure has a sufficiently high average molecular weight cutoff (MWCO) so that the amount of the desired liquid and / or solute (and / or the type of solute) can pass through during the operation of the system. In some embodiments, the average MWCO of the semipermeable membrane of the first membrane separator, the second membrane separator, and / or the third membrane separator is greater than or equal to 50 Daltons, greater than or equal to 75 Daltons, greater than or equal to 100 Daltons, greater than or equal to 150 Daltons, or greater. In some embodiments, the semipermeable membrane of the membrane separator of the present disclosure has a sufficiently low average molecular weight cutoff (MWCO) so that the amount of the desired solute (and / or the type of solute) is retained, so that effective separation is performed. In some embodiments, the average MWCO of the semipermeable membrane of the first membrane separator, the second membrane separator, and / or the third membrane separator is less than or equal to 400 Daltons, less than or equal to 300 Daltons, less than or equal to 250 Daltons, less than or equal to 200 Daltons, or less. Combinations of these ranges are possible (eg, greater than or equal to 50 Daltons and less than or equal to 400 Daltons, greater than or equal to 50 Daltons and less than or equal to 250 Daltons). The average MWCO of a membrane refers to the lowest molecular weight solute at which 90% of the solutes are retained by the membrane.

[0162] In some embodiments, the average MWCO of the semipermeable membrane of the second membrane separator is (e.g., at least 1.05 times, at least 1.1 times, at least 1.2 times, at least 1.5 times, at least 2 times, at least 3 times, at least 5 times, and / or up to 10 times, up to 20 times or more) the average MWCO of the semipermeable membrane of the first membrane separator. In some embodiments, the average MWCO of the semipermeable membrane of the third membrane separator is (e.g., at least 1.05 times, at least 1.1 times, at least 1.2 times, at least 1.5 times, at least 2 times, at least 3 times, at least 5 times, and / or up to 10 times, up to 20 times or more) the average MWCO of the semipermeable membrane of the second membrane separator. The average MWCO of the semipermeable membrane can affect any one of the multiple parameters discussed below, such as solute permeability, salt permeability, rejection, and / or recovery.

[0163] The solute permeability of each membrane separator can be selected based on any of a variety of design criteria such as the desired permeate purity, the desired hydraulic pressure to be used, and the nature of the incoming influent (e.g., the solute concentration of the incoming influent). The solute permeability of a membrane separator can be calculated from the solute flux through the membrane and the concentration of the solute on each side using the following equation [3]:

[0164] J S =B(C R –C P )[3]

[0165] In the above equation, J s represents the ion flux, C R represents the concentration of solute on the retentate side of the membrane, C P represents the concentration of solute on the permeate side of the membrane, and B represents the solute permeability. The solute permeability depends on the type of solute in the retentate inlet stream and the concentration on each side of the membrane.

[0166] In some embodiments, during operation of the method, the solute permeabilities of the first membrane separator and the second membrane separator (and, if present, the third membrane separator) are selected to provide good consistent performance in all membrane separators by taking into account the concentration differences of their respective retentate inlet streams. In some embodiments, the solute permeability of the first membrane separator during the step of delivering the first membrane separator retentate inlet stream to the retentate side of the first membrane separator is different from the solute permeability of the second membrane separator during the step of delivering the second membrane separator retentate inlet stream to the retentate side of the second membrane separator. The difference in solute permeability between the first membrane separator and the second membrane separator can be at least partially due to the use of different semipermeable membranes (e.g., having different pore sizes, MWCO, and / or surface chemical properties) in the first membrane separator and the second membrane separator. In some embodiments, the solute permeability of the first membrane separator during the step of conveying the first membrane separator retentate inlet stream to the retentate side of the first membrane separator and the solute permeability of the second membrane separator during the step of conveying the second membrane separator retentate inlet stream to the retentate side of the second membrane separator differ from each other by at least 5%, by at least 10%, by at least 20%, by at least 50%, and / or by up to 100% or more. In some embodiments, the solute permeability of the second membrane separator during the step of conveying the second membrane separator retentate inlet stream to the retentate side of the second membrane separator is (e.g., at least 1.05 times, at least 1.1 times, at least 1.2 times, at least 1.5 times, at least 2 times, at least 3 times, at least 5 times, or more) the solute permeability of the first membrane separator during the step of conveying the first membrane separator retentate inlet stream to the retentate side of the first membrane separator. In some embodiments, during operation of the first membrane separator, the solute permeability of the first membrane separator is 0. In this context, solute permeability refers to the permeability of all total solutes in the flow. However, in some embodiments, the relationship between the permeabilities of the first membrane separator and the second membrane separator is applicable to one or more specific solute species described in the present disclosure, such as dissolved NaCl and / or dissolved lithium cations.

[0167] When calculating the percentage difference between two values ​​(unless otherwise specified herein), the value that is larger in magnitude is used as the basis for the percentage calculation. For example, if the first value is V 1 , and the second value is V 2 (which is greater than V 1 ), then V 1 and V 2 The percentage difference between ％差异 ) will be calculated as:

[0168]

[0169] And if V ％差异 is X% or less, the first and second values ​​are considered to be within X% of each other, and if V ％差异 is X% or greater, the first value and the second value will be considered to differ from each other by at least X%.

[0170] The water permeability can be calculated from the water flux, pressure difference and osmotic pressure difference as shown in the following equation [5]:

[0171] J W =A(ΔP-Δπ) [5]

[0172] In the above equation [5], J w represents the flux of water through the membrane, ΔP represents the hydraulic pressure difference across the membrane, Δπ represents the osmotic pressure difference across the membrane, and A represents the water permeability.

[0173] The salt permeability percentage under standard conditions of each membrane separator can be selected based on a variety of design criteria such as the desired permeate purity, the hydraulic pressure used, and the properties of the incoming influent (e.g., the solute type and / or concentration of the incoming influent). The salt permeability percentage under standard conditions of the membrane separator is an inherent characteristic of the separator based on the amount of salt (expressed as a percentage) that passes through the semipermeable membrane to the permeate side from the retentate side of the membrane separator under defined reference conditions. The salt permeability percentage under standard conditions of the membrane separator can be determined using the standardized test described in ASTM D4516-19a.

[0174] In some embodiments, the salt permeability under standard conditions of the first membrane separator and the second membrane separator (and, if present, the third membrane separator) used in the operation of the method is selected to provide good and consistent performance in all membrane separators by considering the concentration differences of their respective retentate inlet flows. In some embodiments, the salt permeability percentage under standard conditions of the first membrane separator is different from the salt permeability percentage under standard conditions of the second membrane separator. The difference in salt permeability under standard conditions between the first membrane separator and the second membrane separator can be at least partially due to the use of different semipermeable membranes (e.g., having different pore sizes, MWCO, and / or surface chemical properties) in the first membrane separator and the second membrane separator. In some embodiments, the salt permeability percentage under standard conditions of the first membrane separator and the salt permeability percentage under standard conditions of the second membrane separator differ from each other by at least 5%, at least 10%, at least 20%, at least 50%, and / or differ up to 100% or more. In some embodiments, the salt permeability percentage under standard conditions of the second membrane separator is (e.g., at least 1.05 times, at least 1.1 times, at least 1.2 times, at least 1.5 times, at least 2 times, at least 3 times, at least 5 times, and / or up to 10 times, up to 20 times or more) the salt permeability percentage under standard conditions of the first membrane separator. In some embodiments in which the system further includes a third membrane separator, the salt permeability percentage under standard conditions of the second membrane separator is different from the salt permeability percentage under standard conditions of the third membrane separator. In some embodiments, the salt permeability percentage under standard conditions of the second membrane separator and the salt permeability percentage under standard conditions of the third membrane separator differ from each other by at least 5%, at least 10%, at least 20%, at least 50%, and / or differ by up to 100% or more. In some embodiments, the salt permeability percentage of the third membrane separator under standard conditions is (e.g., at least 1.05 times, at least 1.1 times, at least 1.2 times, at least 1.5 times, at least 2 times, at least 3 times, at least 5 times, and / or up to 10 times, up to 20 times, or more) the salt permeability percentage of the second membrane separator under standard conditions.

[0175] In some embodiments, the first membrane separator, the second membrane separator, and / or the third membrane separator (if present) have a salt permeability percentage under standard conditions that is independently greater than or equal to 0%, greater than or equal to 1%, greater than or equal to 2%, greater than or equal to 5%, greater than or equal to 10%, greater than or equal to 15%, greater than or equal to 20%, greater than or equal to 50%, greater than or equal to 75%, and / or up to 80%, up to 85%, up to 90%, or greater. In some embodiments, the first membrane separator has a relatively low salt permeability percentage under standard conditions. Such a low salt permeability percentage under standard conditions can be useful in embodiments where the first membrane separator operates as a high rejection reverse osmosis separator. In some embodiments, the salt permeability percentage under standard conditions of the first membrane separator is less than or equal to 10%, less than or equal to 5%, less than or equal to 2%, less than or equal to 1%, less than or equal to 0.1%, or less.

[0176] The inherent characteristics of semipermeable membranes, such as salt permeability percentage under standard conditions, pore size and / or MWCO can be selected based on the supplier specifications of commercially available membranes by controlling the synthesis of the membrane and / or by physically and / or chemically modifying existing membranes (e.g., commercially available membranes). As an example of the latter, in some embodiments, a group of identical membranes can be commercially available (or synthetically prepared). The first subset of membranes can be used without further modification. The second subset can be subjected to a first type of modification procedure (e.g., chemical treatment), which enlarges the pores of the membrane and / or modifies the surface chemistry of the membrane in a manner that increases inherent salt permeability (salt permeability percentage under standard conditions), average pore size, and / or MWCO. The third subset of membranes can be subjected to a second different type of modification procedure (e.g., different chemical treatments), which enlarges the pores of the membrane and / or modifies the surface chemistry of the membrane in a manner that increases inherent salt permeability, average pore size, and / or MWCO to a greater degree than those of the second subset of membranes. According to some embodiments, in such a manner, a first subset of membranes can be incorporated into a first membrane separator, a second subset of membranes can be incorporated into a second membrane separator, and a third subset of membranes can be incorporated into a third membrane separator. Each of the first membrane separator, the second membrane separator, and the third membrane separator can then have a different salt permeability percentage under standard conditions and have different permeabilities, rejections, and recoveries in use.

[0177] In some embodiments, the semipermeable membrane comprises cross-linked bonds. For example, the membrane can be a cross-linked polyamide membrane. In some embodiments, the semipermeable membrane includes a cross-linked active layer (for example, a cross-linked polyamide active layer). A method of modifying the semipermeable membrane (for example, so that the inherent salt permeability, average pore size, and / or MWCO increase) is to destroy at least some of the cross-linked bonds of the membrane (for example, at least 0.01 mole percent (mol%), at least 0.1mol%, at least 0.2mol%, at least 0.5mol%, at least 1mol%, at least 2mol%, at least 5mol%, and / or up to 10mol%, up to 20mol% or more). For example, the cross-linked bonds of the membrane (for example, polyamide chains) can be destroyed via physical treatment (for example, heat treatment and / or mechanical destruction) and / or chemical treatment (for example, via treatment with chemical reagents and / or ultraviolet or visible light). The chemical treatment can result in chemical disruption (e.g., via disruption of chemical bonds due to a chemical reaction, disruption of non-covalent interactions such as hydrogen bonds) of at least some (e.g., at least 0.1 mole percent (mol%), at least 0.2 mol%, at least 0.5 mol%, at least 1 mol%, at least 2 mol%, at least 5 mol%, and / or up to 10 mol%, up to 20 mol% or more) of the cross-links. In some embodiments where the semipermeable membrane comprises cross-links (e.g., as part of an active layer), the semipermeable membrane comprises a cross-linked polymer material derived from monomers. In some such embodiments, less than or equal to 99.9 mol% (e.g., less than or equal to 99 mol%, less than or equal to 98 mol%, less than or equal to 95 mol%, and / or as little as 90 mol%, as little as 80 mol%, or less) of the monomers participate in at least one cross-link (e.g., at least in part due to disruption, such as chemical disruption).

[0178] An example of a manner in which at least some of the crosslinks may be disrupted is by treating at least a portion of the membrane with a chemical agent that tends to disrupt the covalent and / or non-covalent bonds within the crosslinks of the membrane. In some embodiments, the chemical agent includes an oxidizing agent. An example of a potential oxidizing agent for use with at least some membranes (e.g., polyamide membranes) is hypochlorite (ClO - ). Hypochlorite can be provided as a solution comprising sodium hypochlorite (NaClO). The cross-linked bonds of the membrane can be destroyed by exposing at least a portion of the membrane to a chemical agent (e.g., an oxidant such as hypochlorite). The duration of exposure and / or the amount of the chemical agent (e.g., the concentration of the agent in the solution in contact with the membrane) can be selected based on the desired degree of destruction of the cross-linked bonds of the membrane. The desired degree of destruction of the cross-linked bonds of the membrane can in turn be based at least on the permeability of the desired semipermeable membrane under certain conditions, the desired average pore size, and / or the desired MWCO.

[0179] The existence and degree of the cross-linked bond of destruction can be determined by checking the semipermeable membrane.For example, the existence and / or quantity of the specific atom or part (for example, terminal functional group) relevant to the chemical dissociation of the cross-linked bond under consideration can be detected and quantified.The existence and / or quantity of such specific atom or part can be observed using for example spectroscopy techniques such as infrared (IR) spectroscopy (for example, Fourier transform infrared (Fourier-Transform Infrared, FTIR) spectroscopy) or X-ray photoelectron spectroscopy (X-ray photoelectronspectroscopy, XPS).For example, XPS can be used to determine the deviation of the atomic ratio of specific atoms compared with the ratio expected in the absence of cross-linking destruction.As an illustrative example, the partially oxidized polyamide film can be measured by using XPS to determine the atomic ratio of oxygen and nitrogen.When polyamide is fully cross-linked, all oxygen atoms and nitrogen atoms in the polyamide polymer form amide groups, obtaining the atomic ratio of oxygen and nitrogen of 1:1. In a completely linear polyamide (thus lacking crosslinks), there is one free carboxyl group for every two amide groups, so the atomic ratio of oxygen to nitrogen is 2: 1. Therefore, measurement of atomic ratios between 1: 1 and 2: 1 can be used to determine the extent of destruction of a partially oxidized polyamide. For example, an atomic ratio of oxygen to nitrogen of 1.5: 1 in a polyamide film indicates that 50 mol% of the crosslinks are destroyed.

[0180] The rejection of each membrane separator can be selected based on any of a variety of design criteria such as the desired permeate purity, the desired hydraulic pressure to be used, and the nature of the incoming influent (e.g., the solute concentration of the incoming influent). The rejection R of the membrane separator can be calculated using the following equation [6] from C R (the concentration of the solute on the retentate side of the membrane) and C P (Concentration of solute on the permeate side of the membrane) is calculated and expressed as a percentage:

[0181] R=[1–(C P / C R )]*100[6]

[0182] In some embodiments, during operation of the method, the rejection (R) of the first membrane separator and the second membrane separator (and, if present, the third membrane separator) is selected to provide good consistent performance in all membrane separators by taking into account the concentration differences of their respective retentate inlet streams. In some embodiments, the first membrane separator has a rejection of at least one solute (or all solutes) (e.g., solutes during the step of conveying the first membrane separator retentate inlet stream to the retentate side of the first membrane separator) that is different from the second membrane separator's rejection of at least one solute (or all solutes) (e.g., solutes during the step of conveying the second membrane separator retentate inlet stream to the retentate side of the second membrane separator). The difference in rejection between the first membrane separator and the second membrane separator can be due at least in part to the use of different semipermeable membranes (e.g., having different pore sizes, MWCOs, and / or surface chemistries) in the first membrane separator and the second membrane separator. In some embodiments, the retention rate of the first membrane separator for at least one solute (or all solutes) (e.g., solutes during the step of conveying the first membrane separator retentate inlet stream to the retentate side of the first membrane separator) and the retention rate of the second membrane separator for at least one solute (or all solutes) (e.g., solutes during the step of conveying the second membrane separator retentate inlet stream to the retentate side of the second membrane separator) differ from each other by at least 5%, differ by at least 10%, differ by at least 20%, differ by at least 50%, and / or differ by up to 100%, or differ by more. In some embodiments, the second membrane separator has a lower retention rate (e.g., at least 5%, at least 10%, at least 20%, at least 50%, at least 75%, at least 90%, or more) for at least one solute (or all solutes) (e.g., solutes during the step of transferring the second membrane separator retentate inlet stream to the retentate side of the second membrane separator) than the first membrane separator has a lower retention rate (e.g., at least 5%, at least 10%, at least 20%, at least 50%, at least 75%, at least 90%, or more) for at least one solute (or all solutes) (e.g., solutes during the step of transferring the first membrane separator retentate inlet stream to the retentate side of the second membrane separator). In some embodiments, the retention rate of the second membrane separator for at least one solute (or all solutes) (e.g., solutes during the step of conveying the second membrane separator retentate inlet stream to the retentate side of the second membrane separator) and the retention rate of the third membrane separator for at least one solute (or all solutes) (e.g., solutes during the step of conveying the third membrane separator retentate inlet stream to the retentate side of the third membrane separator) differ from each other by at least 5%, at least 10%, at least 20%, at least 50%, and / or differ by up to 100%, or more.In some embodiments, the third membrane separator has a lower retention rate (e.g., at least 5%, at least 10%, at least 20%, at least 50%, at least 75%, at least 90%, or more) for at least one solute (or all solutes) (e.g., solutes during the step of transferring the third membrane separator retentate inlet stream to the retentate side of the third membrane separator) than the second membrane separator has a lower retention rate (e.g., at least 5%, at least 10%, at least 20%, at least 50%, at least 75%, at least 90%, or more) for at least one solute (or all solutes) (e.g., solutes during the step of transferring the second membrane separator retentate inlet stream to the retentate side of the second membrane separator).

[0183] In some embodiments, the first membrane separator has a retention rate of greater than or equal to 10%, greater than or equal to 15%, greater than or equal to 20%, greater than or equal to 50%, greater than or equal to 75%, greater than or equal to 80%, greater than or equal to 85%, greater than or equal to 90%, greater than or equal to 95%, greater than or equal to 98%, greater than or equal to 99%, greater than or equal to 99.9%, or greater, for at least one solute (or all solutes) (e.g., solutes during the step of conveying the first membrane separator retentate inlet stream to the retentate side of the first membrane separator, or in some cases specifically lithium cations). In some embodiments, the first membrane separator has a rejection rate of less than or equal to 100%, less than or equal to 99%, less than or equal to 95%, less than or equal to 90%, less than or equal to 85%, less than or equal to 80%, less than or equal to 50%, or less for at least one solute (or all solutes) (e.g., solutes during the step of conveying the first membrane separator retentate inlet stream to the retentate side of the first membrane separator, or in some cases specifically lithium cations). Combinations of these ranges (e.g., greater than or equal to 10% and less than or equal to 100%) are possible.

[0184] In some embodiments, the first membrane separator, the second membrane separator, and / or the third membrane separator (if present) have a rejection rate of at least one solute (or all solutes) (e.g., solutes during the step of conveying the first membrane separator retentate inlet stream to the retentate side of the first membrane separator, or in some cases specifically lithium cations) that is independently greater than or equal to 10%, greater than or equal to 15%, greater than or equal to 20%, greater than or equal to 50%, or greater. In some embodiments, the second membrane separator and / or the third membrane separator (if present) have a rejection rate of at least one solute (or all solutes) (e.g., solutes during the step of conveying the first membrane separator retentate inlet stream to the retentate side of the first membrane separator, or in some cases specifically lithium cations) that is independently less than or equal to 95%, less than or equal to 90%, less than or equal to 85%, less than or equal to 80%, less than or equal to 75%, less than or equal to 60%, less than or equal to 50%, or less. Combinations of these ranges (eg, greater than or equal to 10% and less than or equal to 95%) are possible.

[0185] In the context of the present disclosure, it has been recognized that for systems for performing liquid separations (e.g., for feed stream concentration and / or desalination processes), judicious selection of membranes with different properties can promote good system performance (e.g., in terms of performing the desired separation with fewer components and / or smaller membrane area). Membrane properties such as permeability, salt permeability, pore size, and / or MWCO can affect the observed recovery and rejection. In the context of the present disclosure, it has also been recognized that the recovery and rejection achieved by the membrane separator are affected by the solute concentration (e.g., salinity) of the retentate inlet stream. For example, Figures 8A to 8B The recoveries of four membranes with different permeabilities are shown ( Fig. 8A ) and the retention rate ( Figure 8B ) as a function of feed salinity. Membrane 1 has the lowest permeability and highest rejection, while membrane 4 has the highest permeability and lowest rejection. Such membranes can be obtained from any of a variety of sources, such as by commercial acquisition or by modifying commercially available membranes (e.g., polyamide membranes) to achieve the desired permeability. Figures 8A to 8B As can be seen in FIG. 1 , for each membrane, the recovery and rejection decrease as the feed salinity increases. However, in the context of the present disclosure, it has been recognized that for systems having multiple membrane separators, a substantially constant recovery can be achieved (which may be desirable) regardless of the feed salinity by utilizing membranes having different permeabilities. As an illustrative example, and again with reference to FIG. Fig. 8A , to achieve a 5% recovery, membrane 1 can be used for a feed with 8% salinity, membrane 2 for a feed with 10% salinity, membrane 3 for a feed with 14% salinity, and membrane 4 for a feed with 19% salinity.

[0186] As used herein, the salinity of a liquid stream refers to the weight percentage (wt %) of all dissolved salts in the liquid stream. Salinity can be measured according to any method known in the art. For example, a non-limiting example of a suitable method for measuring salinity is the SM 2540C method. According to the SM 2540C method, a sample containing a certain amount of liquid containing one or more dissolved solids is filtered (for example, by a glass fiber filter), and the filtrate is evaporated to dryness at 180 ℃ in a weighing dish. The increase in dish weight represents the mass of the total dissolved solids in the sample. The salinity of the sample can be obtained by dividing the mass of the total dissolved solids by the mass of the original sample and multiplying the resulting number by 100.

[0187] According to some embodiments, the above-mentioned humidifier is a bubble tower humidifier (e.g., a humidifier in which an evaporation process occurs by direct contact between a water flow and a carrier gas bubble). As discussed in further detail below, a bubble tower humidifier may be associated with certain advantages. In some embodiments, the humidifier is a packed bed humidifier (e.g., a humidifier comprising a packing material). In some cases, the packing material may promote turbulent airflow and / or enhance the contact between a water flow flowing through the packing material in a first direction and a carrier gas flowing in a second substantially opposite direction. A non-limiting example of a suitable packing material is a polyvinyl chloride (PVC) packing material. In some cases, the humidifier is a spray tower (e.g., a humidifier configured to spray water droplets). For example, a nozzle or other spraying device may be positioned at the top of the humidifier so that the water flow sprays downward toward the bottom of the humidifier. The use of a spraying device may advantageously increase the contact degree between the water flow fed to the humidifier and the carrier gas to which the water in the water flow is transported. In some embodiments, the humidifier may be a packed bed humidifier and a spray tower (e.g., the spray tower may include a packing material). In some embodiments, the humidifier is a wetted wall column (eg, a humidifier in which the evaporation process occurs by direct contact between a film or laminar layer of fluid and the carrier gas).

[0188] In some embodiments, the humidifier is configured as a countercurrent flow device. For example, in some cases, the humidifier is configured such that the humidifier liquid inlet is positioned at a first end (e.g., top end) of the humidifier and the humidifier gas inlet is positioned at a second opposite end (e.g., bottom end) of the humidifier. Such a configuration can promote liquid flow through the humidifier in a first direction (e.g., downward) and gas flow through the humidifier in a second substantially opposite direction (e.g., upward), which can advantageously produce high thermal efficiency.

[0189] In some embodiments using a humidification-dehumidification (HDH) device including a humidifier and a dehumidifier as described above, the dehumidifier of the HDH device can have any configuration that allows water to be transferred from a humidified gas stream produced by the humidifier to a substantially pure water stream by a condensation process. In some embodiments, the dehumidifier includes a gas inlet configured to receive a humidified gas stream from the humidifier and / or a liquid inlet configured to receive a substantially pure water stream (e.g., from a source of substantially pure water). The dehumidifier may also include a dehumidifier liquid outlet and / or a dehumidifier gas outlet.

[0190] In certain embodiments, the dehumidifier is a bubble column dehumidifier (e.g., a dehumidifier in which the condensation process occurs by direct contact between a substantially pure water stream and bubbles of humidified gas). In certain cases, the dehumidifier is a surface condenser (e.g., a dehumidifier in which the condensation process occurs by direct contact between the humidified gas and a cooled surface). Non-limiting examples of suitable surface condensers include cooling tube condensers and plate condensers.

[0191] In some embodiments, the dehumidifier is configured as a countercurrent flow device. For example, in some cases, the dehumidifier is configured such that the dehumidifier liquid inlet is positioned at a first end (e.g., top end) of the dehumidifier and the dehumidifier gas inlet is positioned at a second opposite end (e.g., bottom end) of the dehumidifier. Such a configuration can promote liquid flow through the dehumidifier in a first direction (e.g., downward) and gas flow through the dehumidifier in a second substantially opposite direction (e.g., upward), which can advantageously result in high thermal efficiency.

[0192] According to some embodiments, the humidifier is a bubble tower humidifier, and / or the dehumidifier is a bubble tower dehumidifier. In some cases, a bubble tower humidifier and a bubble tower dehumidifier can be related to certain advantages. For example, compared with certain other types of humidifiers and dehumidifiers, a bubble tower humidifier and a dehumidifier can show higher thermodynamic efficiency. It is not desirable to be bound by a specific theory, because bubbles can have a larger surface area that can be used for heat transfer and mass transfer than many other types of surfaces (e.g., metal tubes, liquid films, packing materials), the increased thermodynamic efficiency can be at least partially attributed to the use of bubbles for heat transfer and mass transfer in bubble tower humidifiers and dehumidifiers. In addition, bubble tower humidifiers and dehumidifiers can have certain features that further improve thermodynamic efficiency, including but not limited to relatively low liquid level height, relatively high aspect ratio liquid flow path and multi-stage design.

[0193] In certain systems and methods described herein, suitable bubble column condensers that may be used as dehumidifiers and / or suitable bubble column humidifiers that may be used as humidifiers include those described in: U.S. Patent No. 8,523,985, issued on September 3, 2013 to Govindan et al. and entitled “Bubble-Column Vapor Mixture Condenser”; U.S. Patent No. 8,778,065, issued on July 15, 2014 to Govindan et al. and entitled “Humidification-Dehumidification System Including a Bubble-Column Vapor Mixture Condenser”; U.S. Patent Publication No. 2013 / 0074694, filed on September 23, 2011 to Govindan et al. and entitled “Bubble-Column Vapor Mixture Condenser”; U.S. Patent Publication No. 2013 / 0074694, filed on June 12, 2013 to Govindan et al. and entitled “Multi-Stage Bubble Column Vapor Mixture Condenser” and a Humidifier”; U.S. Patent Publication No. 2014 / 0367871, filed on September 23, 2014, entitled “Desalination Systems and Associated Methods”; U.S. Patent Publication No. 2015 / 0083577, filed on September 23, 2014, entitled “Desalination Systems and Associated Methods”; U.S. Patent Publication No. 2015 / 0129410, filed on September 12, 2014, entitled “Systems Including a Condensing Apparatus Such as a Bubble Column Condenser”; U.S. Patent Application Serial No. 14 / 718,483, filed on May 21, 2015, entitled “Systems Including an Apparatus Comprising both a Humidification Region and a Dehumidification Region” by Govindan et al.; U.S. Patent Application Serial No. 14 / 718,483, filed on May 21, 2015, entitled “Systems Including an Apparatus Comprising both a Humidification Region and a Dehumidification Region with Heat Recovery and / or Intermediate Injection”;U.S. Patent Application Serial No. 14 / 719,239, filed May 21, 2015, by Govindan et al., and entitled “Transiently-Operated Desalination Systems and Associated Methods”; U.S. Patent Application Serial No. 14 / 719,189, filed May 21, 2015, by Govindan et al., and entitled “Transiently-Operated Desalination Systems with Heat Recovery and Associated Methods”; U.S. Patent Application Serial No. 14 / 719,295, filed May 21, 2015, by St. John et al., and entitled “Methods and Systems for Producing Treated Brines”; and U.S. Patent Application Serial No. 14 / 719,299, filed May 21, 2015, by St. John et al., and entitled “Methods and Systems for Producing Treated Brines for Desalination”, each of which is incorporated herein by reference in its entirety for all purposes.;

[0194] In some embodiments of forming substantially pure water, the substantially pure water stream has a relatively low total dissolved ion concentration (e.g., the concentration of all dissolved ions present in the water stream). In some cases, the total dissolved ion concentration of the substantially pure water stream is about 500 mg / L or less, about 200 mg / L or less, about 100 mg / L or less, about 50 mg / L or less, about 20 mg / L or less, about 10 mg / L or less, about 5 mg / L or less, about 2 mg / L or less, about 1 mg / L or less, about 0.5 mg / L or less, about 0.2 mg / L or less, about 0.1 mg / L or less, about 0.05 mg / L or less, about 0.02 mg / L or less, or about 0.01 mg / L or less. According to some embodiments, the total dissolved ion concentration of the substantially pure water stream is substantially zero (e.g., not measurable). In some cases, the total dissolved ion concentration of the substantially pure water stream is in the range of about 0 mg / L to about 500 mg / L, about 0 mg / L to about 200 mg / L, about 0 mg / L to about 100 mg / L, about 0 mg / L to about 50 mg / L, about 0 mg / L to about 20 mg / L, about 0 mg / L to about 10 mg / L, about 0 mg / L to about 5 mg / L, about 0 mg / L to about 2 mg / L, about 0 mg / L to about 1 mg / L, about 0 mg / L to about 0.5 mg / L, about 0 mg / L to about 0.1 mg / L, about 0 mg / L to about 0.05 mg / L, about 0 mg / L to about 0.02 mg / L, or about 0 mg / L to about 0.01 mg / L.

[0195] As used herein, two elements are in fluidic communication with each other (or equivalently, in fluid communication with each other) when a fluid can be transferred from one of the elements to the other of the elements without otherwise changing the configuration of the elements or the configuration of an element (e.g., a valve) between the elements. Two conduits connected by an open valve (thus allowing fluid to flow between the two conduits) are considered to be in fluidic communication with each other. Conversely, two conduits separated by a closed valve (thus preventing fluid from flowing between the conduits) are not considered to be in fluidic communication with each other.

[0196] As used herein, when two elements are connected so that the two elements are fluidly connected to each other under at least one configuration of an element and any intermediate element, the two elements are fluidly connected to each other.Two membrane separators connected by a valve and a conduit that allows flowing between membrane separators under at least one configuration of a valve will be referred to as being fluidly connected to each other.For further explanation, two membrane separators connected by a valve and a conduit that allows flowing between membrane separators under a first valve configuration but does not allow flowing between membrane separators under a second valve configuration are considered to be fluidly connected to each other when the valve is in a first configuration and when the valve is in a second configuration.On the contrary, two membrane separators that are not connected to each other (for example, by a valve, another conduit, or another component) in a manner that will allow fluid to be transported between two membrane separators under any configuration will not be referred to as being fluidly connected to each other.Elements that are fluidly connected to each other are always fluidly connected to each other, but not all elements that are fluidly connected to each other must be fluidly connected to each other.

[0197] A variety of components are described herein as fluid connections. Fluid connections can be direct fluid connections or indirect fluid connections. Typically, when the first region and the second region are fluidly connected to each other and when the composition of the fluid at the second region of the fluid connection is substantially unchanged relative to the composition of the fluid at the first region of the fluid connection (i.e., the weight percentage of the fluid component present in the first region of the fluid connection in the second region of the fluid connection is not greater than 5% different from the weight percentage of the component in the first region of the fluid connection), there is a direct fluid connection between the first region and the second region (and the two regions are referred to as direct fluid connection to each other). As an illustrative example, a flow in which the pressure and temperature of the fluid are regulated but the components of the fluid are not changed will be referred to as direct fluid connection of the first unit operation and the second unit operation. On the other hand, if a separation step that significantly changes the composition of the flow contents during the passage from the first component to the second component and / or a chemical reaction that significantly changes the composition of the flow contents during the passage from the first component to the second component is performed, the flow will not be referred to as direct fluid connection of the first unit operation and the second unit operation. In some embodiments, the direct fluid connection between the first region and the second region can be configured so that the fluid does not undergo a phase change from the first region to the second region. In some embodiments, direct fluid connection can be configured so that at least 50 wt % (or at least 75 wt %, at least 90 wt %, at least 95 wt %, or at least 98 wt %) of the fluid (e.g., liquid) in the first region is delivered to the second region via direct fluid connection. In some embodiments, any of the fluid connections described herein can be a direct fluid connection. In other cases, the fluid connection can be an indirect fluid connection.

[0198] In some embodiments, the feed stream transported to the lithium recovery system initially comprises one or more boron-containing substances (for example, as impurities). In some such embodiments, the feed stream is processed so that at least some (for example, at least 5 wt %, at least 10 wt %, at least 25 wt %, at least 50 wt %, at least 75 wt %, at least 90 wt %, at least 95 wt %, at least 98 wt %, at least 99 wt %, at least 99.9 wt % or all) of the boron-containing substances initially present in the feed stream are removed. The removal of this boron-containing substance can occur before the following liquid removal step. In some embodiments, the concentration of the boron-containing substance dissolved in the feed stream is removed via the boron-containing substance to reduce at least 5 wt %, at least 10 wt %, at least 25 wt %, at least 50 wt %, at least 75 wt %, at least 90 wt %, at least 95 wt %, at least 98 wt %, at least 99 wt %, at least 99.9 wt % or 100 wt % relative to its initial concentration before the boron substance is removed.

[0199] In some embodiments, the following concentrated stream comprises one or more boron-containing substances (e.g., as impurities). In some such embodiments, the concentrated stream is treated so that at least some (e.g., at least 5 wt%, at least 10 wt%, at least 25 wt%, at least 50 wt%, at least 75 wt%, at least 90 wt%, at least 95 wt%, at least 98 wt%, at least 99 wt%, at least 99.9 wt%, or all) of the boron-containing substances initially present in the concentrated stream are removed. The removal of such boron-containing substances can occur before, during, and / or after other impurity removal steps (e.g., removal of non-lithium cations) described in the present disclosure. In some embodiments, the concentration of the dissolved boron-containing substances in the concentrated stream is reduced by at least 5 wt%, at least 10 wt%, at least 25 wt%, at least 50 wt%, at least 75 wt%, at least 90 wt%, at least 95 wt%, at least 98 wt%, at least 99 wt%, at least 99.9 wt%, or 100 wt% relative to its initial concentration before the boron substance is removed via the boron-containing substances.

[0200] Non-limiting examples of boron-containing species that may be present in the feed stream and / or concentrate stream (and that may be removed) include non-ionic species (e.g., boric acid (H 3 BO 3 )) and / or ionic species (e.g., tetrahydroxyborate (B(OH) 4 - )).

[0201] Any of a variety of techniques may be employed to remove boron-containing species. For example, the feed stream and / or the concentrate stream may be exposed to a boron selective medium. Fig.13AA schematic diagram of a lithium recovery system 100 is shown in which a boron selective medium 145 is configured to process a feed stream 104 by exposing it to a feed stream portion 104A and removing at least some boron-containing species, thereby producing a feed stream portion 104B (at least a portion of which can form part or all of a first membrane separator retentate inlet stream 105). The concentration of boron-containing species in feed stream portion 104B can be lower than that of feed stream portion 104A (e.g., at least 25%, at least 50%, at least 75%, at least 90%, at least 95%, at least 98%, at least 99%, or more, on a mass basis), or feed stream portion 104B can be free of boron-containing species. A portion (e.g., an outlet) of the boron selective medium can be fluidly connected to the retentate side of the first membrane separator.

[0202] Fig. 13B A schematic diagram of a lithium recovery system 100 is shown in which a boron selective medium 145 is configured to process a concentrate stream 108 by exposing it to a feed stream portion 108A and removing at least some boron-containing species, thereby producing a concentrate stream portion 104B (at least a portion of which can form part or all of a decontaminated stream 124). The concentration of boron-containing species in the concentrate stream portion 108B can be lower than that of the concentrate stream portion 108A (e.g., at least 25%, at least 50%, at least 75%, at least 90%, at least 95%, at least 98%, at least 99%, or more on a mass basis), or the concentrate stream portion 108B can be free of boron-containing species. A portion (e.g., an inlet) of the boron selective medium can be fluidly connected to the retentate side of the first membrane separator (or the retentate side of the second membrane separator or the third membrane separator, or a portion of the humidifier, if present).

[0203] Boron selective medium can be, for example, a boron selective membrane. As another example, a boron selective medium can be a boron selective resin. For example, a boron selective medium can be a boron selective ion exchange medium such as a boron selective ion exchange membrane and / or an ion exchange resin. Boron-containing material can be bonded to at least a portion of a boron selective medium (e.g., a boron selective membrane and / or a resin). Binding can occur by chelation, adsorption, and / or any other suitable mechanism. In some cases, a boron selective medium can include N-methylglucosamine functional groups and / or benzyl-dimethylethanolamine functional groups.

[0204] Non-limiting examples of techniques for removing boron-containing species from liquids (e.g., water) are described in U.S. Patent Application Publication No. 2020 / 0231473, published on July 23, 2020, and entitled “Systems and Methods for Removal of Boron from Water, Such as Oilfield Wastewater,” which is incorporated herein in its entirety.

[0205] In an exemplary embodiment, lithium hydroxide is obtained from a brine rich in dissolved lithium cations and dissolved chloride anions (eg, salt lake brine) using the methods and systems described in this disclosure. Fig. 9 A schematic process diagram for solid lithium hydroxide recovery is shown. The feed stream is first subjected to a softening process, wherein scaling ions (e.g., multivalent cations, silica) are removed using one or more of chemical treatment (e.g., with lime, dolomite, activated alumina, ferric chloride, sodium hypochlorite, and / or polymers (e.g., polyelectrolytes), ion exchange, or membrane softening (e.g., nanofiltration or electrodialysis). Prior to softening, the feed stream may be at a temperature in the range of 25° C. to 50° C., at a pH in the range of 2 to 14, and at a total dissolved solids concentration of 14593 mg / L (including a lithium cation concentration of 10 mg / L to 680 mg / L). After softening, the feed stream has a temperature in the range of 25° C. to 40° C. (e.g., 25° C. to 36° C.), a pH of about 5.5, and a total dissolved solids concentration (TDS) of 14593 mg / L. Then, the feed flow was approximately 2.5 m 3 / hour is fed to the retentate side of the first membrane separator ("RO") and hydraulic pressure is applied to perform the reverse osmosis process. The retentate of the first membrane separator is then 3 / hour flow rate is fed to the retentate side of the second membrane separator (high permeability reverse osmosis unit, "high permeability reverse osmosis, HiRO"). The retentate fed to HiRO has a temperature in the range of 25°C to 40°C (e.g., 25°C to 36°C) and a total dissolved solids concentration of 37,000 mg / L. The permeates from both RO (total dissolved solids concentration less than 500 mg / L) and HiRO can be discharged from the system (e.g. Fig. 9), but in some cases, the permeate from the HiRO can be recycled back to the RO or the retentate inlet stream of the HiRO. The retentate from the HiRO has a temperature in the range of 25°C to 50°C (e.g., 25°C to 40°C or 25°C to 36°C) and a total dissolved solids concentration of 200,000 mg / L. The retentate from the HiRO is fed to a HDH device ("HDH") comprising a packed bed humidifier and a multi-stage bubble tower dehumidifier. The HDH produces fresh water (which can be discharged from the system) and brine having a temperature of less than 100°C and a total dissolved solids concentration of 250,000 mg / L. The brine from the HDH is fed to a forced circulation evaporator (FCC) where non-lithium salt separation is performed. In the FCC, the brine is heated at atmospheric pressure until it begins to boil, and continues to boil at a temperature of 100°C to 160°C while the brine is circulated, producing precipitation of a mixture of potassium chloride and sodium chloride. The mother liquor produced by the FCC (with a total dissolved solids concentration of 300,000 mg / L to 400,000 mg / L) is fed to a cooler (e.g., a portion of a crystallizer). In the cooler, the temperature is reduced to 30°C to 35°C, and further precipitation of NaCl and KCl occurs while maintaining substantially the same amount of dissolved lithium ions in the mother liquor. The precipitate is separated from the mother liquor (e.g., by decantation). Additional lithium cations can be recovered by washing the precipitate with a small amount of feed water and returning that amount of feed water to the feed stream. The precipitate can be sent for further processing (e.g., via a centrifuge / agitated thin film dryer crystallizer) to obtain solid NaCl and KCl with low moisture. The lithium-rich mother liquor / supernatant from the FCC / cooler is fed to an electrolysis unit. In the electrolysis unit, Cl is produced. 2 and acid. 2 The acid is discharged from the system and can be recycled back to the softening process for the feed stream. The electrolysis unit produces a brine rich in LiOH, at a temperature in the range of 30°C to 35°C and a total dissolved solids concentration of 10,000 mg / L to 60,000 mg / L. The LiOH-rich brine is transferred from the electrolysis unit to a second HDH unit, where the LiOH-rich brine is further concentrated in a humidifier (while a dehumidifier produces fresh water). The further concentrated LiOH-rich brine (which in some cases can have a total dissolved salt concentration of greater than 250,000 mg / L) is transferred to another FCC / crystallizer, where solid LiOH salt is produced. The solid LiOH salt can then be pneumatically conveyed and packaged in a form-fill-seal system.

[0206] In another exemplary embodiment, solid lithium hydroxide is obtained from a solution rich in dissolved lithium cations and dissolved sulfate and carbonate anions using the methods and systems described in the present disclosure. Fig.10A schematic process diagram for solid lithium hydroxide recovery is shown. The feed stream is first subjected to a leaching and precipitation process, during which sulfate anions and carbonate anions are replaced via chemically induced precipitation and / or leaching, while chloride anions are retained and / or chloride anions are added. Prior to leaching and precipitation, the feed stream may be at a temperature in the range of 25°C to 50°C, a pH in the range of 2 to 14, and a total dissolved solids concentration of <1%. After leaching and precipitation, the feed stream has a temperature in the range of 25°C to 40°C (e.g., 25°C to 36°C), a pH of about 5.5, and a total dissolved solids concentration of <1%. The feed stream is then precipitated at about 2.5 m 3 / hour is fed to the retentate side of the first membrane separator ("RO") and hydraulic pressure is applied to perform the reverse osmosis process. The retentate of the first membrane separator is then 3 / hour is fed to the retentate side of the second membrane separator (high permeability reverse osmosis device, "HiRO"). The retentate fed to the HiRO has a temperature in the range of 25°C to 40°C (e.g., 25°C to 36°C) and a total dissolved solids concentration of <2% to 5%. The permeate from both the RO (total dissolved solids concentration less than 500 mg / L) and the HiRO can be discharged from the system (e.g. Fig.10 ), but in some cases, the permeate from the HiRO can be recycled back to the RO or the retentate inlet stream of the HiRO. The retentate from the HiRO has a temperature in the range of 25°C to 50°C (e.g., 25°C to 40°C or 25°C to 36°C) and a total dissolved solids concentration of 200,000 mg / L. Fig.10 The rest of the process shown in this example is the same as Fig. 9 The process shown in is the same as above.

[0207] In another example embodiment, solid lithium hydroxide is obtained from a solution derived from lithium-ion batteries (eg, discarded / spent lithium-ion batteries) using the methods and systems described in the present disclosure. Fig.11 A schematic process diagram for solid lithium hydroxide recovery is shown. A feed stream provided directly or indirectly by one or more lithium ion batteries is first subjected to a mechanochemical and / or leaching process (e.g., via the addition of hydrochloric acid, sulfuric acid, nitric acid, acetic acid, and / or citric acid), while chloride anions are retained and / or chloride anions are added. Prior to the mechanochemical and / or leaching process, the feed stream may be at a temperature in the range of 25°C to 50°C (e.g., 25°C to 40°C or 25°C to 36°C), a pH in the range of 2 to 14, and a total dissolved solids concentration of <1%. After the mechanochemical and / or leaching process, the feed stream has a temperature in the range of 25°C to 40°C (e.g., 25°C to 36°C), a pH of about 5.5, and a total dissolved solids concentration of <1%. The feed stream is then leached at about 2.5 m3 / hour is fed to the retentate side of the first membrane separator ("RO") and hydraulic pressure is applied to perform the reverse osmosis process. The retentate of the first membrane separator is then 3 / hour is fed to the retentate side of the second membrane separator (high permeability reverse osmosis device, "HiRO"). The retentate fed to the HiRO has a temperature in the range of 25°C to 40°C (e.g., 25°C to 36°C) and a total dissolved solids concentration of <2% to 5%. The permeate from both the RO (total dissolved solids concentration less than 500 mg / L) and the HiRO can be discharged from the system (e.g. Fig.11 ), but in some cases, the permeate from the HiRO can be recycled back to the RO or the retentate inlet stream of the HiRO. The retentate from the HiRO has a temperature in the range of 25°C to 50°C (e.g., 25°C to 40°C or 25°C to 36°C) and a total dissolved solids concentration of 200,000 mg / L. Fig.11 The rest of the process shown in this example is the same as Fig. 9 The process shown in is the same as above.

[0208] In another example embodiment, a lithium-containing stream is concentrated (eg, contains dissolved lithium cations in an amount of at least 10 mg / L) using the methods described in this disclosure. Fig.12 A schematic process diagram of such a lithium ion concentration process is shown. The feed stream is first subjected to a softening process, where chemical treatment, clarification, multimedia filtration and ion exchange are used to remove scaling ions (e.g., multivalent cations, silica). Fig.12 The addition of ferric chloride (FeCl 3 ), sodium hydroxide (NaOH) and polymer flocculants to induce hardness precipitation and promote flocculation. The flocculated precipitate ( Fig.12 The "sludge" in the feed stream is settled in a clarifier and a clarified supernatant stream is removed. The clarified supernatant is pH adjusted by adding hydrochloric acid (HCl) and subjected to ultrafiltration ( Fig.12 The flocculated precipitate ("sludge") that settles from the supernatant in the clarifier is dewatered in a filter press and the resulting dewatered solids are discharged from the system. Backwash waste from the ultrafilter ( Fig.12 "UF backwash" in the ion exchange regeneration process) and backwash waste from the ion exchange regeneration process ( Fig.12The softened feed stream is treated with sodium bisulfate ("SBS"), antiscalant, and sodium hydroxide, pumped through a cartridge filter, combined with a portion of the RO retentate stream to form the RO inlet stream, pressurized to 7.5 MPa, and introduced into the first membrane separator ( Fig.12 The hydraulic pressure on the retentate side of the RO membrane overcomes the osmotic pressure of the RO inlet stream, causing the RO permeate stream to diffuse through the RO membrane, leaving behind a RO retentate stream. The RO permeate stream is pressurized again and introduced into the second membrane separator ( Fig.12 The retentate side of the polishing RO ("polishing RO") is supplied to the retentate of the polishing RO. The hydraulic pressure on the retentate side of the polishing RO overcomes the osmotic pressure of the RO permeate stream, causing the polishing RO permeate stream containing substantially pure water to diffuse through the polishing RO membrane, leaving a polishing RO retentate stream. The polishing RO permeate stream is delivered to the customer as a final product, and the polishing RO retentate stream is combined with the softened feed stream. A portion of the RO retentate stream is combined with the softened feed stream to form the RO inlet stream, and the remainder is introduced into a high permeability reverse osmosis unit ( Fig.12 The retentate side of the third membrane separator of the HiRO ("HiRO") as the HiRO retentate inlet stream. The HiRO system includes a plurality of (e.g., at least 2, at least 5, at least 10 or more) membranes arranged with their retentate and permeate sides connected in series. The hydraulic pressure difference across each HiRO membrane overcomes the osmotic pressure difference, and water and at least some solutes diffuse from the HiRO retentate flow across the membrane to form a HiRO permeate outlet stream, leaving a HiRO retentate outlet stream. The HiRO retentate outlet stream is depressurized, and a first portion of the stream is discharged from the system.

[0209] International Patent Application Publication No. WO2022 / 203706, filed on August 25, 2021 as International Patent Application No. PCT / US2021 / 47614 and published on September 29, 2022, entitled “Lithium Recovery from Liquid Streams”, is hereby incorporated by reference in its entirety for all purposes. U.S. Patent Application Publication No. 2023-0001355, filed on July 2, 2021 as U.S. Patent Application No. 17 / 305,289 and published on January 5, 2023, entitled “Membranes with Controlled Porosity for Serial Filtration”, is hereby incorporated by reference in its entirety for all purposes. U.S. Provisional Patent Application No. 63 / 411,079, filed on September 28, 2022, and entitled “Liquid Separation Using Solute-Permeable Membranes and Related Systems” (Attorney Docket No. G0859.70055US01), is hereby incorporated by reference in its entirety for all purposes. U.S. Patent Application No. 18 / 315,130, filed on May 10, 2023, and entitled “Liquid Separation Using Solute-Permeable Membranes and Related Systems” is hereby incorporated by reference in its entirety for all purposes.

[0210] U.S. Provisional Patent Application No. 63 / 411,075, filed on September 28, 2022, and entitled “Lithium Recovery from Liquid Streams Using Solute-Permeable Membranes,” is incorporated herein by reference in its entirety for all purposes.

[0211] The following examples are intended to illustrate certain embodiments of the invention, but are not intended to illustrate the full scope of the invention.

[0212] Example 1

[0213] This example describes the concentration of lithium-containing streams having various salinities and dissolved lithium cation concentrations using a membrane separator comprising a semipermeable membrane having relatively high solute and water permeabilities (referred to in this example as a "HiRO" unit).

[0214] A synthetic lithium cation-rich brine with a salinity of about 7.5% was prepared with the concentrations listed in Table 1 to simulate the characteristics of a feed stream after initial concentration using a conventional high cutoff reverse osmosis (RO) unit. The concentrations were determined using mass spectrometry.

[0215] Table 1. Characteristics of initial feed brine to HiRO unit.

[0216]

[0217]

[0218] The brine was pressurized to 1000 psi (6,895 kPa) and fed to a HiRO unit prepared according to the method described in U.S. Patent Application No. 17 / 305,289, producing a concentrate stream exiting the HiRO retentate side and a permeate stream exiting the HiRO permeate side. The concentrate stream and permeate stream had the following characteristics as determined via mass balance, shown in Tables 2 and 3, respectively.

[0219] Table 2. Characteristics of the concentrate stream formed by treating the initial 7.5% feed brine through a HiRO unit.

[0220] parameter Concentrate water quality unit Cl 64951 ppm Li 10944 ppm K 147 ppm Na 4462 ppm <![CDATA[SO 4 ]]> 634 ppm TDS 81138 ppm

[0221] Table 3. Characteristics of the permeate stream formed by treating the initial 7.5% feed brine through a HiRO unit.

[0222]

[0223]

[0224] The same experiment was conducted at salinities of 10%, 12.5%, 15%, 17% and 20%, with each test being conducted with the same ratio of constituent ions to roughly estimate the progressive concentration across the retentate side of the multi-stage HiRO system. The results of the final concentrate characteristics after processing 20% ​​brine through the HiRO unit are shown in Table 4.

[0225] Table 4. Characteristics of the concentrate stream formed by treating the initial 20% feed brine through a HiRO unit.

[0226] parameter Concentrate water quality unit Cl 175536 ppm Li 30352 ppm K 613 ppm Na 11975 ppm <![CDATA[SO 4 ]]> 1824 ppm TDS 220299 ppm

[0227] The experiments in this example demonstrate that a membrane separator having a relatively high permeability that allows a portion of dissolved lithium cations to pass through its semipermeable membrane can be used to effectively concentrate lithium in a lithium-rich feed stream having a relatively high overall salinity while using relatively modest applied hydraulic pressure.

[0228] Although several embodiments of the present invention have been described and illustrated herein, a person of ordinary skill in the art will readily appreciate a variety of other means and / or structures for performing the functions described herein and / or obtaining the results and / or one or more advantages described herein, and each of such changes and / or modifications is considered to be within the scope of the present invention. More generally, it will be readily understood by those skilled in the art that all parameters, dimensions, materials, and configurations described herein are intended to be exemplary, and that the actual parameters, dimensions, materials, and / or configurations will depend on one or more specific applications using the teachings of the present invention. Those skilled in the art will recognize or be able to determine many equivalents of the specific embodiments of the present invention described herein using only routine experiments. Therefore, it should be understood that the foregoing embodiments are presented only by way of example, and within the scope of the appended claims and their equivalents, the present invention can be implemented in a manner other than specifically described and claimed. The present invention relates to each individual feature, system, product, material, and / or method described herein. In addition, if such features, systems, products, materials, and / or methods do not contradict each other, any combination of two or more such features, systems, products, materials, and / or methods is included within the scope of the present invention.

[0229] As used herein in the specification and in the claims, the phrase "at least a portion" means part or all. According to certain embodiments, "at least a portion" can mean at least 1 weight %, at least 2 weight %, at least 5 weight %, at least 10 weight %, at least 25 weight %, at least 50 weight %, at least 75 weight %, at least 90 weight %, at least 95 weight %, or at least 99 weight %, and / or in certain embodiments up to 100 weight %.

[0230] Unless explicitly stated to the contrary, as used herein in the specification and claims, nouns without quantifiers should be understood to mean "at least one".

[0231] The phrase "and / or" as used herein in the specification and in the claims should be understood to mean "either or both" of the elements so combined, i.e., elements that are present together in some cases and separately in other cases. Unless expressly indicated to the contrary, other elements may optionally be present in addition to the elements specifically identified by the "and / or" clause, whether related or unrelated to those specifically identified elements. Thus, as a non-limiting example, when used in conjunction with open language such as "comprising," a reference to "A and / or B" may refer to A without B (optionally including elements other than B) in one embodiment; to B without A (optionally including elements other than A) in another embodiment; to both A and B (optionally including other elements) in yet another embodiment; and so on.

[0232] As used herein in the specification and in the claims, "or" should be understood to have the same meaning as "and / or" as defined above. For example, when the items in the list are separated, "or" or "and / or" should be interpreted as inclusive, that is, including at least one of multiple elements or lists of elements, but also including more than one, and optionally other unlisted items. Only explicitly indicating the opposite terms, such as "only one of" or "exactly one of", or "consisting of when used in claims, will refer to including exactly one element in multiple elements or lists of elements. Usually, when there are exclusive terms such as "one of", "one of...", "only one of..." or "exactly one of..." in front, the term "or" as used herein should only be interpreted as representing exclusive selection (that is, one or another but not two). When used in claims, "essentially consisting of..." should have the common meaning used in the field of patent law.

[0233] As used herein in the specification and in the claims, the phrase "at least one" when referring to a list of one or more elements should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of the individual elements and each element specifically listed in the list of elements, and not excluding any combination of elements in the list of elements. This definition also allows that elements other than the elements specifically identified in the list of elements to which the phrase "at least one" refers may optionally be present, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, "at least one of A and B" (or equivalently, "at least one of A or B", or equivalently, "at least one of A and / or B") may refer, in one embodiment, to at least one A, optionally including more than one A, without B (and optionally including elements other than B); in another embodiment, to at least one B, optionally including more than one B, without A (and optionally including elements other than A); in yet another embodiment, to at least one A, optionally including more than one A, and at least one B, optionally including more than one B (and optionally including other elements); and so on.

[0234] In the claims and in the foregoing specification, all transitional phrases such as "comprising," "including," "with," "having," "containing," "involving," "having," etc. are to be understood as open-ended, i.e., meaning including, but not limited to. Only the transitional phrases "consisting of" and "consisting essentially of" shall be closed or semi-closed transitional phrases, respectively, as set forth in Section 2111.03 of the U.S. Patent Office Manual of Patent Examining Procedures.

Claims

1. A method, include: Removing at least a portion of the liquid from a feed stream comprising liquid, dissolved lithium cations, and dissolved non-lithium cations to form a concentrated stream having a higher concentration of dissolved lithium cations than the feed stream, wherein the removing comprises: (a) delivering a first membrane separator retentate inlet stream comprising at least a portion of the feed stream to the retentate side of the first membrane separator such that: a first membrane separator retentate outlet stream exiting the retentate side of the first membrane separator, the first membrane separator retentate outlet stream having a concentration of dissolved lithium cations greater than a concentration of dissolved lithium cations in the first membrane separator retentate inlet stream, and at least a portion of the liquid from the first membrane separator retentate inlet stream is transported from the retentate side of the first membrane separator through the semipermeable membrane of the first membrane separator to the permeate side of the first membrane separator; (b) conveying a second membrane separator retentate inlet stream comprising at least a portion of the first membrane separator retentate outlet stream to the retentate side of the second membrane separator such that: a second membrane separator retentate outlet stream exiting the retentate side of the second membrane separator, the second membrane separator retentate outlet stream having a concentration of dissolved lithium cations greater than a concentration of dissolved lithium cations in the second membrane separator retentate inlet stream, and at least a portion of the liquid from the second membrane separator retentate inlet stream, at least a portion of the dissolved lithium cations, and at least a portion of the dissolved non-lithium cations are transported from the retentate side of the second membrane separator through the semipermeable membrane of the second membrane separator to the permeate side of the second membrane separator; and (c) delivering a humidifier liquid inlet stream comprising at least a portion of the second membrane separator retentate outlet stream to a humidifier and causing at least a portion of the liquid of the humidifier liquid inlet stream to evaporate within the humidifier to produce a humidified gas stream and a humidifier liquid outlet stream having a higher dissolved lithium cation concentration than the humidifier liquid inlet stream, such that at least a portion of the humidifier liquid outlet stream is part of the concentrate stream; and At least some of the dissolved non-lithium cations are removed from the concentrate stream to form a decontaminated concentrate stream having an atomic ratio of dissolved lithium cations to dissolved non-lithium cations greater than the atomic ratio of dissolved lithium cations to dissolved non-lithium cations in the concentrate stream.

2. A method, include: Removing at least a portion of the liquid from a feed stream comprising liquid, dissolved lithium cations, and dissolved non-lithium cations to form a concentrated stream having a higher concentration of dissolved lithium cations than the feed stream, wherein the removing comprises: (a) delivering the first membrane separator retentate inlet stream to the retentate side of the first membrane separator such that: a first membrane separator retentate outlet stream exiting the retentate side of the first membrane separator, the first membrane separator retentate outlet stream having a concentration of dissolved lithium cations greater than a concentration of dissolved lithium cations in the first membrane separator retentate inlet stream, and at least a portion of the liquid from the first membrane separator retentate inlet stream is transported from the retentate side of the first membrane separator through the semipermeable membrane of the first membrane separator to the permeate side of the first membrane separator; (b) conveying a second membrane separator retentate inlet stream comprising at least a portion of the first membrane separator retentate outlet stream to the retentate side of the second membrane separator such that: a second membrane separator retentate outlet stream exiting the retentate side of the second membrane separator, the second membrane separator retentate outlet stream having a concentration of dissolved lithium cations greater than a concentration of dissolved lithium cations in the second membrane separator retentate inlet stream, and at least a portion of the liquid, at least a portion of the dissolved lithium cations, and at least a portion of the dissolved non-lithium cations from the second membrane separator retentate inlet stream are transported from the retentate side of the second membrane separator through the semipermeable membrane of the second membrane separator to the permeate side of the second membrane separator, where a portion of the liquid, a portion of the dissolved lithium cations, and a portion of the dissolved non-lithium cations form a portion or all of the second membrane separator permeate outlet stream that is transported out of the permeate side of the second membrane separator; (c) delivering a third membrane separator retentate inlet stream comprising at least a portion of the second membrane separator retentate outlet stream to the retentate side of the third membrane separator such that: a third membrane separator retentate outlet stream exiting the retentate side of the third membrane separator, the third membrane separator retentate outlet stream having a concentration of dissolved lithium cations greater than the concentration of dissolved lithium cations of the third membrane separator retentate inlet stream, and at least a portion of the liquid, at least a portion of the dissolved lithium, and at least a portion of the dissolved non-lithium cations from the third membrane separator retentate inlet stream are transported from the retentate side of the third membrane separator through the semipermeable membrane of the third membrane separator to the permeate side of the third membrane separator where a portion of the liquid, a portion of the dissolved lithium cations, and a portion of the dissolved non-lithium cations form a portion or all of the third membrane separator permeate outlet stream that is transported out of the permeate side of the third membrane separator; and (d) delivering a humidifier liquid inlet stream comprising at least a portion of the third membrane separator retentate outlet stream to a humidifier, and causing at least a portion of the liquid of the humidifier liquid inlet stream to evaporate within the humidifier to produce a humidified gas stream and a humidifier liquid outlet stream having a higher concentration of dissolved lithium cations than the humidifier liquid inlet stream, such that at least a portion of the humidifier liquid outlet stream is part of the concentrate stream; and removing at least some of the dissolved non-lithium cations from the concentrate stream to form a decontaminated concentrate stream having an atomic ratio of dissolved lithium cations to dissolved non-lithium cations greater than the atomic ratio of dissolved lithium cations to dissolved non-lithium cations in the concentrate stream; in: the first membrane separator retentate inlet stream comprises at least a portion of the second membrane separator permeate outlet stream and / or at least a portion of the third membrane separator permeate outlet stream; and The second membrane separator retentate inlet stream and / or the third membrane separator retentate inlet stream comprises at least a portion of the feed stream.

3. A method, include: Removing at least a portion of the liquid from a feed stream comprising the liquid and dissolved lithium cations to form a concentrate stream having a higher concentration of dissolved lithium cations than the feed stream, wherein the removing comprises: A first membrane separator retentate inlet stream comprising at least a portion of the feed stream is delivered to the retentate side of the first membrane separator such that: a first membrane separator retentate outlet stream exiting the retentate side of the first membrane separator, the first membrane separator retentate outlet stream having a concentration of dissolved lithium cations greater than a concentration of dissolved lithium cations in the first membrane separator retentate inlet stream, and at least a portion of the liquid from the first membrane separator retentate inlet stream is transported from the retentate side of the first membrane separator through the semipermeable membrane of the first membrane separator to the permeate side of the first membrane separator; and A second membrane separator retentate inlet stream comprising at least a portion of the first membrane separator retentate outlet stream is delivered to the retentate side of the second membrane separator such that: a second membrane separator retentate outlet stream exiting the retentate side of the second membrane separator, the second membrane separator retentate outlet stream having a concentration of dissolved lithium cations greater than the concentration of dissolved lithium cations of the second membrane separator retentate inlet stream, such that at least a portion of the second membrane separator retentate outlet stream is a portion of the concentrate stream, and at least a portion of the liquid from the second membrane separator retentate inlet stream and at least a portion of the dissolved lithium cations are transported from the retentate side of the second membrane separator through the semipermeable membrane of the second membrane separator to the permeate side of the second membrane separator; in: The concentration of dissolved lithium cations in the feed stream is greater than or equal to 10 mg / L, and A ratio of a concentration of dissolved lithium cations in the concentrate stream to a concentration of dissolved lithium cations in the feed stream is greater than or equal to 4.

4. A method, include: Removing at least a portion of the liquid from a feed stream comprising the liquid and dissolved lithium cations to form a concentrate stream having a higher concentration of dissolved lithium cations than the feed stream, wherein the removing comprises: The first membrane separator retentate inlet stream is delivered to the retentate side of the first membrane separator such that: a first membrane separator retentate outlet stream exiting the retentate side of the first membrane separator, the first membrane separator retentate outlet stream having a concentration of dissolved lithium cations greater than a concentration of dissolved lithium cations in the first membrane separator retentate inlet stream, and at least a portion of the liquid from the first membrane separator retentate inlet stream is transported from the retentate side of the first membrane separator through the semipermeable membrane of the first membrane separator to the permeate side of the first membrane separator; A second membrane separator retentate inlet stream comprising at least a portion of the first membrane separator retentate outlet stream is delivered to the retentate side of the second membrane separator such that: a second membrane separator retentate outlet stream exiting the retentate side of the second membrane separator, the second membrane separator retentate outlet stream having a concentration of dissolved lithium cations greater than a concentration of dissolved lithium cations of the second membrane separator retentate inlet stream, and at least a portion of the liquid and at least a portion of the dissolved lithium cations from the second membrane separator retentate inlet stream are transported from the retentate side of the second membrane separator through the semipermeable membrane of the second membrane separator to the permeate side of the second membrane separator where a portion of the liquid and a portion of the dissolved lithium cations form a portion or all of the second membrane separator permeate outlet stream that is transported out of the permeate side of the second membrane separator; and A third membrane separator retentate inlet stream comprising at least a portion of the second membrane separator retentate outlet stream is delivered to the retentate side of the third membrane separator such that: a third membrane separator retentate outlet stream exiting the retentate side of the third membrane separator, the third membrane separator retentate outlet stream having a concentration of dissolved lithium cations greater than the concentration of dissolved lithium cations of the third membrane separator retentate inlet stream, such that at least a portion of the third membrane separator retentate outlet stream is a portion of the concentrate stream, and at least a portion of the liquid and at least a portion of the dissolved lithium cations from the third membrane separator retentate inlet stream are transported from the retentate side of the third membrane separator through the semipermeable membrane of the third membrane separator to the permeate side of the third membrane separator, where the portion of the liquid and the portion of the dissolved lithium cations form part or all of the third membrane separator permeate outlet stream that is transported out of the permeate side of the third membrane separator; in: the first membrane separator retentate inlet stream comprises at least a portion of the second membrane separator permeate outlet stream and / or at least a portion of the third membrane separator permeate outlet stream; the second membrane separator retentate inlet stream and / or the third membrane separator retentate inlet stream comprising at least a portion of the feed stream; The concentration of dissolved lithium cations in the feed stream is greater than or equal to 10 mg / L, and A ratio of a concentration of dissolved lithium cations in the concentrate stream to a concentration of dissolved lithium cations in the feed stream is greater than or equal to 4.

5. The method of any one of claims 1 to 4, wherein the first membrane separator retentate inlet stream comprises a portion of the first membrane separator retentate outlet stream.

6. A method according to any one of claims 1 to 5, wherein the portion of the liquid and the portion of the dissolved lithium cations transported from the retentate side of the second membrane separator through the semipermeable membrane of the second membrane separator to the permeate side of the second membrane separator form part or all of the second membrane separator permeate outlet flow.

7. The method of any one of claims 2, 4 and 6, wherein the first membrane separator retentate inlet stream comprises at least a portion of the second membrane separator permeate outlet stream.

8. The method of any one of claims 1 to 7, wherein at least a portion of the dissolved lithium cations from the first membrane separator retentate inlet stream are transported from the retentate side of the first membrane separator through the semipermeable membrane of the first membrane separator to the permeate side of the first membrane separator.

9. The method according to any one of claims 1 to 8, wherein the solute permeability of the first membrane separator during the step of conveying the first membrane separator retentate inlet flow to the retentate side of the first membrane separator is different from the solute permeability of the second membrane separator during the step of conveying the second membrane separator retentate inlet flow to the retentate side of the second membrane separator.

10. The method according to any one of claims 1 to 9, wherein the solute permeability of the first membrane separator during the step of conveying the first membrane separator retentate inlet flow to the retentate side of the first membrane separator and the solute permeability of the second membrane separator during the step of conveying the second membrane separator retentate inlet flow to the retentate side of the second membrane separator differ from each other by at least 5%.

11. The method of any one of claims 1 to 10, wherein the salt permeability percentage under standard conditions of the first membrane separator is different from the salt permeability percentage under standard conditions of the second membrane separator, wherein the salt permeability percentage under standard conditions is determined using ASTM D4516-19a. 12 . The method according to claim 1 , wherein the salt permeability percentage under standard conditions of the first membrane separator and the salt permeability percentage under standard conditions of the second membrane separator differ from each other by at least 5%. 13 . The method according to claim 1 , wherein the salt permeability percentage of the second membrane separator under standard conditions is greater than the salt permeability percentage of the first membrane separator under standard conditions.

14. The method according to any one of claims 1 to 13, wherein the salt permeability percentage of the second membrane separator under standard conditions is at least 1.05 times the salt permeability percentage of the first membrane separator under standard conditions. 15 . The method according to claim 1 , wherein the rejection rate of the solute by the second membrane separator on the retentate side is smaller than the rejection rate of the solute by the first membrane separator on the retentate side.

16. The method of any one of claims 1 to 15, wherein the second membrane separator has a retention rate of the solute on the retentate side that is at least 5% less than the retention rate of the solute on the retentate side of the first membrane separator.

17. The method according to any one of claims 1 to 16, wherein the average molecular weight cut-off (MWCO) of the semipermeable membrane of the second membrane separator is greater than the average molecular weight cut-off of the semipermeable membrane of the first membrane separator.

18. The method according to any one of claims 1 to 17, wherein the average molecular weight cutoff (MWCO) of the semipermeable membrane of the second membrane separator is at least 1.05 times the average molecular weight cutoff (MWCO) of the semipermeable membrane of the first membrane separator.

19. The method according to any one of claims 1 to 18, wherein the average MWCO of the semipermeable membrane of the first membrane separator and / or the semipermeable membrane of the second membrane separator is less than or equal to 400 Daltons.

20. The method according to any one of claims 1 to 19, wherein the average MWCO of the semipermeable membrane of the first membrane separator and / or the semipermeable membrane of the second membrane separator is greater than or equal to 50 Daltons.

21. The method according to any one of claims 1 to 20, wherein the first membrane separator and / or the second membrane separator has a rejection rate of less than or equal to 95% for the dissolved lithium cations.

22. The method according to any one of claims 1 to 21, wherein the first membrane separator and / or the second membrane separator has a rejection rate of the dissolved lithium cations greater than or equal to 10%.

23. The method according to any one of claims 1 to 22, wherein the semipermeable membrane of the first membrane separator and / or the semipermeable membrane of the second membrane separator have cross-links, wherein at least some of the cross-links are broken.

24. The method according to any one of claims 1 to 23, wherein the semipermeable membrane of the first membrane separator and / or the semipermeable membrane of the second membrane separator have cross-links, wherein at least some of the cross-links are chemically destroyed.

25. A method according to any one of claims 1 to 24, wherein the semipermeable membrane of the first membrane separator and / or the semipermeable membrane of the second membrane separator comprises an active layer, the active layer comprises a cross-linked polymer material derived from monomers, and wherein less than or equal to 99.9 mol % of the monomers participate in cross-linking bonds.

26. The method of any one of claims 1, 3, and 5 to 25, wherein the method further comprises delivering a third membrane separator retentate inlet stream to the retentate side of the third membrane separator such that: a third membrane separator retentate outlet stream exiting the retentate side of the third membrane separator, the third membrane separator retentate outlet stream having a concentration of dissolved lithium cations greater than the concentration of dissolved lithium cations of the third membrane separator retentate inlet stream, and at least a portion of the liquid and at least a portion of the dissolved lithium cations from the third membrane separator retentate inlet stream are transported from the retentate side of the third membrane separator through the semipermeable membrane of the third membrane separator to the permeate side of the third membrane separator, where the portion of the liquid and the portion of the dissolved lithium cations form part or all of the third membrane separator permeate outlet stream that is transported out of the permeate side of the third membrane separator; in: The third membrane separator retentate inlet stream comprises at least a portion of the second membrane separator retentate outlet stream.

27. The method of any one of claims 2, 4, and 5 to 26, wherein the first membrane separator retentate inlet stream comprises at least a portion of the third membrane separator permeate outlet stream.

28. The method of any one of claims 1 and 5 to 27, wherein step (c) further comprises condensing at least a portion of the liquid in the humidified gas in a dehumidifier to produce a condensed liquid stream.

29. The method of any one of claims 2 and 5 to 27, wherein step (d) further comprises condensing at least a portion of the liquid in the humidified gas in a dehumidifier to produce a condensed liquid stream.

30. The method of any one of claims 28 to 29, wherein the dehumidifier is a bubble column dehumidifier.

31. The method of any one of claims 1 to 2 and 5 to 30, wherein the humidifier is a packed bed humidifier or a bubble column humidifier.

32. The process of any one of claims 1 to 31, wherein the feed stream comprises anions selected from one or more of chloride, sulfate, carbonate, bicarbonate, nitrate, borate, phosphate, bromide, citrate, oxyanions, and hydride ions.

33. The method of any one of claims 3 to 32, wherein the feed stream comprises dissolved non-lithium cations.

34. The method of claim 33, wherein the method further comprises removing at least some of the dissolved non-lithium cations from the concentrate stream to form a decontaminated concentrate stream having an atomic ratio of dissolved lithium cations to dissolved non-lithium cations greater than the atomic ratio of dissolved lithium cations to dissolved non-lithium cations in the concentrate stream.

35. The method of any one of claims 1 to 2 and 5 to 34, wherein the non-lithium cation is selected from one or more of a sodium cation, a potassium cation, a magnesium cation, and a calcium cation.

36. The method of any one of claims 1 to 2 and 5 to 35, wherein removing at least some of the dissolved non-lithium cations from the concentrate stream produces the decontaminated concentrate stream having a lower concentration of the dissolved non-lithium cations than the concentrate stream.

37. The method of any one of claims 1 to 2 and 5 to 36, wherein removing at least some of the dissolved non-lithium cations from the concentrate stream results in a ratio of the concentration of dissolved lithium cations in the decontaminated concentrate stream to the total concentration of all dissolved non-lithium cations that is at least 1.1 times the ratio of the concentration of dissolved lithium cations in the concentrate stream to the total concentration of all dissolved non-lithium cations.

38. The process of any one of claims 1 to 2 and 5 to 37, wherein the concentration of dissolved lithium cations in the feed stream is greater than or equal to 10 mg / L.

39. The method of any one of claims 1 to 2 and 5 to 38, wherein the ratio of the concentration of dissolved lithium cations in the concentrate stream to the concentration of dissolved lithium cations in the feed stream is greater than or equal to 4.

40. The method of any one of claims 1 to 2 and 5 to 39, wherein removing at least some of the dissolved non-lithium cations from the concentrate stream comprises increasing the temperature of the concentrate stream to form a heated concentrate stream so that a quantity of solid non-lithium-containing salt comprising at least a portion of the non-lithium cations is formed.

41. The method of claim 40, wherein the non-lithium-containing salt comprises a cation selected from one or more of sodium and potassium, and an anion selected from one or more of chloride, sulfate, carbonate, bicarbonate, nitrate, borate, phosphate, bromide, citrate, oxyanion, and hydride.

42. The method of any one of claims 40 to 41, wherein removing at least some of the dissolved non-lithium cations from the concentrate stream further comprises reducing the temperature of the heated concentrate stream so that additional amounts of the solid non-lithium containing salt are formed.

43. A method according to any one of claims 1 to 2 and 5 to 42, wherein the decontamination concentrated stream contains dissolved first anions, and the method further comprises applying a voltage to an electrochemical cell containing at least a portion of the decontamination concentrated stream so that at least a portion of the first anions are replaced by second, different anions, thereby forming an electrochemically treated solution, the electrochemically treated solution comprising the liquid, the dissolved lithium cations, and a concentration of the dissolved second anions greater than the concentration of the dissolved second anions in the decontamination concentrated stream.

44. The method of claim 43, wherein the first anion is a chloride ion.

45. The method of any one of claims 43 to 44, wherein the second anion is a hydroxide ion.

46. ​​The method of any one of claims 43 to 45, further comprising evaporating at least a portion of the liquid from the electrochemically treated solution within a humidifier to produce a second humidified gas flow and a second humidifier liquid outlet flow having a higher concentration of dissolved lithium cations and dissolved second anions than the concentration of dissolved lithium cations and dissolved second anions in the electrochemically treated solution.

47. The method of any one of claims 43 to 46, further comprising obtaining a solid lithium salt comprising at least a portion of the lithium cations and at least a portion of the second anions from the second humidifier liquid outlet stream.

48. The method of any one of claims 1 to 47, wherein the feed stream initially comprises one or more boron-containing species, and the method comprises removing at least some of the one or more boron-containing species from the feed stream.

49. The method of any one of claims 1 to 48, wherein the concentrate stream initially comprises one or more boron-containing species, and the method comprises removing at least some of the one or more boron-containing species from the concentrate stream.

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