System and method for augmented lithium extraction

Abstract

Provided herein is a method for the direct extraction of lithium ions from a liquid using an adsorbent. More specifically, after the lithium-containing liquid is passed through the adsorbent, a second lithium-containing booster liquid is passed through the adsorbent, thus augmenting the amount of lithium that is subsequently eluted from the adsorbent.

Description

[0001] SYSTEM AND METHOD FOR AUGMENTED LITHIUM EXTRACTION

[0002] CROSS-REFERENCE TO RELATED APPLICATION The present application claims priority under 35 U.S.C. 365(c) to

[0003] U.S. Provisional Appln. No. 63 / 665,795, filed on June 28, 2024, which is incorporated herein by reference in its entirety.

[0004] FIELD OF THE INVENTION Provided herein is a method for the direct extraction of lithium ions from a liquid using an adsorbent. More specifically, after the lithium-containing liquid is passed through the adsorbent, a second lithium-containing booster liquid is passed through the adsorbent, thus augmenting the amount of lithium that is adsorbed in the adsorbent and subsequently eluted from the adsorbent.

[0005] BACKGROUND OF THE INVENTION

[0006] Several patents, patent applications and publications are cited in this description in order to more fully describe the state of the art to which this invention pertains. The entire disclosure of each of these patents, patent applications, and publications is incorporated by reference herein.

[0007] Lithium (Li) is a key component in high-energy-density lithium-ion batteries. Lithium-ion batteries are used in a variety of applications including electric vehicles, computers, and energy storage devices, among others. An increase of the global demand for lithium is anticipated in the foreseeable future. Currently, industrial-scale Li-extraction technology employs chemical treatments followed by evaporation-based processes to recover lithium from different natural and recycled sources, which is time consuming and requires a large-footprint operation. Moreover, a large amount of water evaporation is needed to recover lithium, and most of the natural lithium sources are in arid regions with limited clean water availability. To speed up the evaporation process and recover water, engineered processes such as thermal evaporation followed by condensation have been applied, but these are still energy inefficient.

[0008] Various processes to recover lithium from natural and recycled sources by adsorbing and eluting lithium ions have been described. Some of these processes further include a step of purifying or concentrating the source or eluant using membranes, such as reverse osmosis or nanofiltration membranes. For example, U.S. Pat. No. 10,604,414 describes a process for recovery of lithium from a geothermal brine using ion exchange and reverse osmosis methods. U.S. Pat. No. 10,648,061 describes passing a lithium source into and out of a bed of sorbent composed of hydrated alumina intercalated with a lithium halide; washing the bed of sorbent to obtain a lithium eluent of increased lithium concentration; and treating this eluent with nanofiltration, reverse osmosis, and forward osmosis among others to obtain a high purity lithium salt solution. U.S. Patent Appln. Publn.

[0009] No. 2022 / 00055910 describes a method of isolating lithium as lithium hydroxide or lithium carbonate via sorption / desorption and other purification methods. Various streams, including some lithium-containing streams, are recycled to the sorption / desorption process. U.S. Patent Appln. Publn.

[0010] No. 2023 / 0357941 describes processes in which the lithium product stream is fractionated to control the purity. Portions of the product stream are concentrated, and portions of it are recycled. Finally, PCT Inti. Appln. Publn. No. W02024 / 016080 describes a process in which saltwater is subjected to direct lithium extraction. The eluant is concentrated by reverse osmosis and then subjected to a second direct lithium extraction step. A portion of the second depleted lithium stream may be added to the saltwater.

[0011] Clearly, a need remains for more efficient direct lithium extraction methods, in particular methods that provide a good yield, improved purity, and superior energy efficiency.

[0012] SUMMARY OF THE INVENTION

[0013] Accordingly, provided herein is a method of lithium extraction. The method includes providing a brine stream comprising lithium ions and passing a portion of the brine stream through an adsorbent bed assembly to extract lithium ions from the brine stream. After passing the portion of the brine stream, a portion of a booster stream is passed through the adsorbent bed assembly and followed by an eluant that is passed through the at least one adsorbent bed assembly to obtain a lithium-extract.

[0014] The brine stream comprises dissolved lithium ions and dissolved nonlithium cations. The brine stream has a molar concentration ratio of the dissolved non-lithium cations to the dissolved lithium ions that is greater than 1.0. The booster stream is a stream that has a lithium-ion concentration higher than that of the brine stream; or a stream with a molar concentration ratio of the dissolved non-lithium cations to the dissolved lithium ions that is greater than the corresponding ratio in the brine stream.

[0015] In some improved embodiments, the booster stream comprises a portion of the brine stream.

[0016] BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Fig. 1 is a schematic drawing of a system suitable for use in the method described herein to extract lithium from a given brine stream with augmented lithium adsorption realized by providing a booster stream;

[0018] Fig. 2 is a schematic drawing of another system suitable for the lithium extraction method described herein;

[0019] Fig. 3 is a schematic drawing of yet another system suitable for use in the lithium extraction method described herein; Fig. 4 is a schematic drawing of yet another system suitable for use in the lithium extraction method described herein;

[0020] Fig. 5 is a schematic drawing of yet another system suitable for use in the lithium extraction method described herein;

[0021] Fig. 6 is a schematic drawing of another system suitable for lithium extraction method described herein with augmented lithium adsorption from a given mixed stream prepared using the given brine stream and the booster stream; Fig. 7 is a schematic drawing of yet another system suitable for lithium extraction method described herein with augmented lithium adsorption from a given mixed stream;

[0022] Fig. 8 is a graph of the concentration of various cations vs. the bed volume of brine in the lithium-depleted brine leaving a column;

[0023] Fig. 9 is a graph of the concentration of various cations vs. the bed volume of eluent in the lithium-enriched eluent leaving a column;

[0024] Fig. 10 is a graph of the concentration of various cations vs. the bed volume of brine in the lithium-depleted brine leaving a column after augmented lithium loading; and

[0025] Fig. 11 is a graph of the concentration of various cations vs. the bed volume of eluent in the lithium-enriched eluent leaving a column after augmented lithium loading. DETAILED DESCRIPTION

[0026] A system and method for augmented lithium extraction are provided herein. The method comprises providing a brine stream with a dissolved mass of lithium ions. Preferably, the brine stream is aqueous. Preferably, the concentration of lithium ion in the brine stream, or in waters of interest for use as the brine stream, is between 0.05 g / L and 6 g / L, more preferably between 0.1 g / L and 3 g / L. For a given volume, the dissolved mass of lithium ion may be calculated by multiplying the volume by the concentration of dissolved lithium ion. For example, the dissolved mass of lithium in 10ml of solution having a concentration of 2g / L of lithium ions is 0.01 L x 2g / L = 0.02g lithium. The brine stream may comprise non-lithium cations. The non-lithium cations may be monovalent cations such as, but not limited to, sodium (Na), potassium (K), cesium (Cs), and rubidium (Rb) ions. The non-lithium cations may be multivalent cations such as, but not limited to, ions of Mg, Ca, Mn, Fe, Cu, Al, Sr, Ba, Ti, Zn, Cd, and Pb in any oxidation state that is stable in aqueous solution. The brine stream may also comprise mono- and multivalent anions. Non-limiting examples of monovalent anions include Cl; Br, F; I-, OH; and HCOa'. Non-limiting examples of multi-valent anions include SO-r, CO3=, POc and HPOF. The brine stream may also comprise soluble organics, dissolved materials, and suspended particles such as, but not limited to, colloidal silica and clay.

[0027] The brine stream may be used as obtained from a natural source such as a salt lake, a Salar or a geothermal brine-source; alternatively, it may be derived from clay mining or from a hard rock deposit. The brine stream may be generated synthetically by acid-digesting a lithium-containing material such as, but not limited to, lithium-ion batteries, solar panels, solar storage devices, computers, laptops, and like devices. Alternatively, the brine stream may be a processed feed which is generated by processing a natural resource brine or a synthetically generated brine. In addition, some preferred synthetic brines are described in U.S. Patent No. 11,371 ,118, for example.

[0028] Preferably, the anions in the brine stream are monovalent anions only or dominated by monovalent anions. As used in this context, a fluid is “dominated by” a certain anion when the number of moles of that anion exceeds the number of moles of every other individual anion in the fluid. For instance, a brine stream containing anions of only chloride (35.45 amu) and sulfate (96.06 amu) can be considered as a brine stream that is dominated by monovalent anions when it includes more than 27 wt% of chloride anions based on the total weight of the dissolved anions. Naturally occurring South American Salar and greater China salt lakes streams are examples of brine streams that are dominated by monovalent anions. Preferably, the monovalent anions in the brine stream are chloride only, or at least 90 mol%, at least 95 mol%, or at least 97 mol% chloride.

[0029] The brine stream has a dissolved lithium molar concentration and a dissolved non-lithium cation molar concentration, and said molar concentrations define a molar concentration ratio of dissolved non-lithium cations to dissolved lithium ions. Preferably, the dissolved non-lithium cation(s) comprise one or more ions selected from the group consisting of soluble ions of boron, sodium, potassium, calcium, magnesium, barium, zinc, aluminum, manganese, iron, and strontium. For a given dissolved ion, the corresponding molar concentration can be calculated by dividing the measured ion mass per unit volume of solution by the molar mass of the ion. For instance, in a brine stream of volume 1 liter containing 150 mg of Li (6.941 amu), 2300 mg of Na (22.989 amu) and 480 mg of Mg (24.305 amu), the molar concentration values are 21.61 , 100.05, and 19.75 mmol / L, respectively. For said brine stream, the dissolved lithium molar concentration is 21.61 mmol / L (or 0.02161 mol / L). For said brine stream, the dissolved nonlithium cation molar concentration is 119.80 mmol / L (or 0.1198 mol / L = 0.10005 moi / L + 0.01975 mol / L)). For said brine stream, the molar concentration ratio of the dissolved non-lithium cation to the dissolved lithium ions is 5.54( = 119.8 / 21.61 ).

[0030] The dissolved non-lithium cation molar concentration in the brine stream is at least 0.05 mol / L (or 50 mmol / L). The dissolved non-lithium cation molar concentration in the brine stream is preferably at least 0.1 mol / L, more preferably at least 1 mol / L, even more preferably at least 10 mol / L.

[0031] The method described herein is advantageous when the molar concentration ratio of the dissolved non-lithium cation to the dissolved lithium ions in the brine is greater than 1.0, preferably greater than 10.0, more preferably greater than 100.0.

[0032] The method described herein includes a step of passing a portion of the brine stream through an apparatus comprising at least one adsorbent bed assembly, each of said adsorbent bed assemblies comprising at least one adsorbent bed or adsorbent column, and each of said adsorbent bed(s) or adsorbent column(s) comprising an adsorbent. The adsorbent bed assembl(ies) are housed within an apparatus. When said apparatus includes more than one adsorbent bed assembly, the apparatus is selected from a system wherein the assemblies are arranged in parallel, in series, or in a configuration comprising assemblies arranged in parallel and assemblies arranged in series. Moreover, within each adsorbent bed assembly comprising one or more beds or columns or at least one bed and at least one column, the bed(s) or column(s) may be arranged in parallel, in series, or in a configuration comprising beds or columns arranged in parallel and beds or columns arranged in series. In addition, each of said one or more beds or columns independently comprises an adsorbent bed selected from the group consisting of a fixed bed, a packed bed, a continuous countercurrent adsorption / desorption system, a lead-lag arrangement of columns, a continuous countercurrent ion exchange system, a simulated moving bed column system, a moving bed column system such as a Higgins loop, a continually stirred adsorption tank, and a continually stirred ion exchange tank. Use of the continuous countercurrent adsorption / desorption system as the adsorption bed is specifically advantageous, as described in U.S. Pat. No. 10,604,414 B2. That being said, the method described herein is not limited to any specific adsorption apparatus configuration or selection of adsorption bed(s) or column(s) housed within said apparatus.

[0033] The adsorption bed preferably comprises a lithium-selective adsorbent. As used herein, the term “adsorb”, whether alone or in combined form such as for example “adsorption” or “adsorbent”, refers to the action of selectively sequestering lithium ions from a solution or to a material that selectively sequesters lithium ions from a solution. Accordingly, the term “adsorb” includes any selective sequestration regardless of its mechanism, which may be accomplished by adsorption, ion exchange, intercalation, another mechanism, or a combination of two or more mechanisms. Similarly, the terms “adsorb into” and “adsorb onto” [a material] are synonymous and used interchangeably herein to refer to any selective sequestration regardless of its mechanism. Accordingly, suitable lithium selective adsorbents include, without limitation, a lithium aluminum intercalate, a lithium aluminum layered double hydroxide chloride, a layered double hydroxide modified activated alumina, a layered double hydroxide modified activated boehmite, a layered double hydroxide loaded or synthesized within the pores of a porous support such as an ion exchange resin or copolymer or molecular sieve or zeolite or porous material, a blend of lithium aluminum intercalates with polymers, a lithium manganese oxide, a lithium manganese oxide that has been blended with at least one polymer, a lithium titanium oxide, a lithium titanium oxide that has been blended with at least one polymer, an immobilized crown ether, or a combination of two or more of these lithium-selective adsorbents. More preferably, the lithium-selective adsorbent contains lithium halides intercalated between layers of aluminum hydroxide. It is advantageous to use LiX'2AI(OH)3-nH2O, wherein n is 0 to 10 and X is a halogen. Examples of suitable lithium-selective adsorbents of this formula are described in U.S. Pat. No. 11 ,371 ,118, for example.

[0034] The lithium-selective adsorbent suitable for use herein may further comprise one or more polymer(s) used as binders, supports or scaffolds. Suitable polymers are described in U.S. Pat. No. 11 ,371 ,118. Preferred polymers include, without limitation, polystyrene, polyacrylic acid, polymethylmethacrylate, polyacrylamide, polyvinylidene fluoride, polyvinyl fluoride, polyvinylchloride, polyvinyl alcohol, polytetrafluoroethylene, related polymers, and combinations of two or more of these polymers.

[0035] The method described herein includes a step wherein the adsorbent extracts lithium from the portion of the brine stream passing through it. The terms “extract(s)” and “extraction” as used herein are defined as the movement or transfer of a species or ion. For example, the phrase “the adsorbent extracts lithium from the brine stream” means that lithium ions are moved or transferred from the brine stream onto the adsorbent. Similarly, when an eluant is passed through the adsorbent bed assembly, a lithium- extract is produced by moving or transferring the lithium ions from the adsorbent to the eluant. In some methods, both lithium ions and non-lithium cations may be extracted from the brine stream onto the adsorbent. In some preferred methods, only lithium ions and monovalent non-lithium cations may be extracted from the brine stream onto the adsorbent. In some more preferred methods, only lithium ions may be extracted from the brine stream onto the adsorbent. Suitable adsorbents preferentially adsorb lithium ions and allow the greater part of the other dissolved non-lithium cations to leave the adsorbent bed assembly. Therefore, the lithium-extract produced by desorbing the lithium ions from the adsorbent contains primarily lithium ions and a much lesser amount of any non-lithium cations than was included in the brine. Consequently, the molar concentration ratio of the dissolved non-lithium cations to the dissolved lithium ions in the lithium-extract is less than said ratio in the brine stream.

[0036] In some methods, it is particularly beneficial if the eluant volume used to produce the lithium-extract is less than liquid volumes processed during the adsorption step(s). This will result in enrichment where the lithium-ion concentration in the lithium-extract is higher than the same in the brine stream. For example, if a 100L of liquid volume with a lithium concentration of 100 mg / L is processed through the adsorbent, and if a 10L liquid volume used as the eluant, then the lithium ion-concentration in the lithium-extract will be 1000 mg / L (assuming 100% mass transfer efficiency during the adsorption and desorption steps).

[0037] It is expected that as various brine-based lithium resources are subjected to direct lithium extraction, the concentration of lithium in the resource will gradually decrease. As this occurs, the efficiency and therefore the profitability of extraction of lithium from the resource will also gradually decrease. The reasons are firstly that the performance of direct lithium extraction technologies that utilize a lithium-selective adsorbent will be greatly affected by concentration of lithium. Secondly, the volume of brine to be processed must be increased in order to produce the same quantity of lithium. It is known that for adsorbent materials, the quantity of lithium that will be bound to the adsorbent (its capacity) is strongly influenced by the concentration of lithium in the brine, with higher concentrations correlating to higher capacities for lithium. Also, for a given lithium concentration in the brine feed, the binding capacity improves when a higher amount of nonlithium cations is present (i.e., when the molar concentration ratio of the nonlithium cations to the lithium ions is higher). Higher capacities for lithium will tend to allow higher concentrations of lithium in the lithium-extract stream (and eventually in all downstream operations to prepare the final product) as well as higher concentrations of lithium relative to the other species in the brine (i.e. a higher purity of lithium in the lithium-extract). Therefore, methods of increasing the lithium concentration in the brine will allow lithium-selective sorbents to maintain high capacity for lithium, which will allow for the maintenance of the economic profitability of the direct lithium extraction process.

[0038] Examples of references that describe the adsorption isotherms and binding capacities of lithium-selective sorbents include, without limitation, Farrokrrouz et al., Sorption-based Lithium extraction from diverse brines using aluminium-based adsorbent, Journal of Water Process Engineering 72 (2025) 107593 (available at https: / / doi.Org / 10.1016 / i.jwpe.2025.107593):

[0039] Qian C. et al., Adsorption performance and mechanism of Li+ from brines using iithium / aluminum layered double hydroxides-SiO2 bauxite composite adsorbents, Front. Chem. 11 :1265290 (2023); Qin Y., et al., Adsorption of lithium ions from aqueous solution by magnetic aluminum-based adsorbents, PLoS ONE 18(12): e0295269 (2023) (available at https: / / doi.org / 10.1371 / iournal.pone.0295269); and Adrah, K., et al. Mechanistic Understanding of Sieving Lithium Ions Using a Biobased Sorbent Technology for Sustainable Lithium Reclamation and Cleansing Brines, ACS Omega 2024, 9, 21917-21929 (available at https: / / doi.org / 10.1021 / acsomega.3c09716).

[0040] It is desired to improve adsorption capacity of the adsorbent to improve process efficiency. Accordingly, provided herein is a method to improve capacity by using a booster stream. The booster stream is selected from the group consisting of: (a) a stream with a lithium-ion concentration higher than the lithium ion concentration of the brine stream, and (b) a stream wherein the molar concentration ratio of the dissolved non-lithium cations to the dissolved lithium ions is greater than the molar concentration ratio of the dissolved nonlithium cations to the dissolved lithium ions in the brine stream.

[0041] Any stream satisfying conditions (a) or (b) declared above can be used as the booster stream. Examples of suitable booster streams include, without limitation, a different brine stream (or streams) that may be obtained from another source; a synthetic brine stream prepared to be used as the booster stream; a stream generated by processing any stream within the method and system described herein to be used as the booster stream (e.g. processing a portion of the lithium-extract to generate the booster stream); or a combination of two or more of these streams in any ratio that produces a combined stream that satisfies condition (a) or (b).

[0042] Referring now to the drawings, wherein like reference numerals designate corresponding structure throughout the views, and referring in particular to Fig. 1 , a system 10 suitable to treat the brine stream 12 to extract lithium using the method described herein is depicted. In this system 10, a portion 14 of the brine stream 12 passes through the adsorbent bed assembly 20. The adsorbent assembly 20 contains at least one adsorbent bed or column 23 housing an adsorbent 24 which selectively extracts lithium ions from the brine stream and produces a lithium-depleted brine stream 16.

[0043] In the following step , a booster stream 34 enters the adsorbent bed assembly 20 and passes through the adsorbent 24 where lithium ions are extracted resulting in a lithium-depleted booster stream 36. In the final step, an eluant stream 52 enters the adsorbent bed assembly 20 and desorbs lithium ions from the adsorbent 24 to produce a lithium-extract 54 eluting from the adsorbent bed assembly 20.

[0044] The adsorbent bed assembly 20 contains at least one adsorbent bed or column and preferably multiple adsorbent beds or columns. The terms “bed” and “column”, whether used alone or in combined form, such as, for example, “bed volume” and “column volume", are synonymous and used interchangeably herein. It follows that, when a bed or a column is described herein, it is to be understood that either a bed or a column is suitable for that use, unless specifically stated otherwise in limited circumstances. Accordingly, in an alternative statement, the adsorbent bed assembly 20 may contain at least one adsorbent bed, at least one adsorbent column, or a combination of two or more adsorbent bed(s) or adsorbent column(s).

[0045] For any given adsorbent column, the steps described above take place sequentially; however, the adsorbent bed assembly may alternatively be operated with continuous adsorptions of the brine and booster streams and continuous desorption to produce lithium-extract by using multiple columns and switching the steps among the columns.

[0046] Still referring to Fig. 1, a portion 56 of the lithium extract 54, which is produced from the lithium-extract 54 by regulation via a valve 90’ (preferably a 3-way ball valve), is routed for further processing. The remaining portion of the lithium-extract that does not undergo processing, stream 58, exits the system 10, preferably to undergo treatment via unit operations for one or more of lithium to non-lithium cation separation, lithium-ion concentration, and precipitation of lithium salt(s). As depicted in Fig. 1 , the system 10 also comprises at least one hyperfiltation unit that provides a means to generate the booster stream. The hyperfiltration unit comprises a high-pressure pump 30 fluidly connected to a first hyperfiltration stage 40 housing a hyperfiltration membrane 42. The stream 56, via pump 30, is pressurized and sent to the first hyperfiltration stage 40 where the membrane 42 processes the portion 56 of the lithium extract 54 to produce a lithium-lean solution 46 and a lithium-rich solution 44.

[0047] A valve 90” (preferably a 3-way ball valve) may divert a portion 48 of the lithium-rich solution 44 towards a holding tank 50. Concomitantly, a nondiverted portion of the lithium-rich solution 44, designated as the stream 49, may exit the system. To maximize the system efficiency, from at least 50% up to the entirety of the lithium-rich solution 44 is diverted and becomes the stream 48 which is routed to the holding tank 50 and eventually used as the booster stream 34. In this way, a portion of the lithium-extract (stream 56) undergoes processing (through a first hyperfiltration stage 40) to form a lithium-rich solution (stream 44) and a portion of the said solution (stream 48) forms a part of the booster stream 34. The first hyperfiltration stage 40 may be of any size suitable to the parameters of the desired process. For example, it may be small (e.g. one or more small test cells containing a few cm2total area of active membrane 42) or it may comprise many vessels in series or parallel, each vessel containing more than 100 m2area of membrane 42. Alternatively, intermediate values may be chosen for the area of the membrane(s) 42. The membrane 42 is a hyperfiltration membrane and the term “hyperfiltration” used herein refers to reverse osmosis and to nanofiltration. A reverse osmosis membrane may be defined as a membrane that is typically impermeable to virtually ail dissolved salts and organic molecules with molecular weight greater than approximately 70 Daltons. A nanofiltration membrane may be defined as a semi-permeable membrane that typically rejects particles in the nanometer range as well as organic molecules having molecular weights greater than approximately 200 to 500 Daltons. Further, the nanofiltration membrane preferentially rejects di- and multivalent ions and large neutral species and passes monovalent ions and small neutral species. Preferably, the hyperfiltration membrane 42 is a reverse osmosis membrane. The lithium-rich solution 44 comprises the liquid (and anything present in the liquid in dissolved form) that does not pass through or that is rejected by the hyperfiltration (preferably RO) membrane 42. The majority of the lithium ions and other ions (including divalent cations) present in the stream 56 partitions into the lithium-rich solution 44, because reverse osmosis membranes reject almost all ionic species. Thus, the divalent cation concentration in the lithium-rich solution 44 is higher than the divalent cation concentration in the lithium-extract 54. Also, the lithium ion concentration in the lithium-rich solution 44 is higher than the lithium concentration in the lithium extract 54 or in the brine stream 12. The lithium-lean solution 46 comprises the liquid that passes through the membrane 42 under pressure and is primarily water (with trace amounts of dissolved species). This lithium lean-solution 46 exits the hyperfiltration unit and further exits the system 10 for reuse purpose (not shown). Suitable eluants include, without limitation, aqueous solutions such as a dilute solution comprising a halide salt, a dilute solution comprising a nonhalide salt, an acidic solution, a buffer solution, and a combination of two or more of these solutions. Preferably, the eluant is selected from the group consisting of a dilute solution of a halide salt, a dilute solution of a non-halide salt, an acidic solution, and a buffer solution. It is preferred that the halide anion present in the eluant is a chloride, as the majority of the natural brine resources are rich in chloride ions. Moreover, when the eluant comprises chloride ion, it avoids the complexity of adding a different type of anion to the lithium-extract. Accordingly, it is more preferable that LiCI is the halide salt in the eluant stream. Often, a stream generated in the downstream operations is repurposed as the eluant stream. For example, a low ion-containing stream generated during the lithium-concentrating step or a tailing fraction of the lithium-extract obtained during the desorption step with very low Li concentration may be recycled as the eluant. The temperature of the eluant is preferably >15°C, >25°C, >40°C,

[0048] >60°C, >80°C, or up to 120°C. In general, the higher the temperature of the eluant, the higher the lithium desorption efficiency, and the higher the lithium concentration in the lithium-extract. Significantly, however, there is a temperature above which no benefit to desorption is obtained. At these excessively high temperatures, heat is dissipated to the atmosphere. Therefore, the maximum desorption temperature is set according to the engineering environment and heat loss rate. Moreover, the higher the desorption temperature, the higher the temperature for the fluid entering the semipermeable membrane system. As a result, at these higher temperatures the entire lithium extraction plant has a higher temperature gradient between the processing fluid and the ambient environment, and thus the heat loss rate is higher. Advantageously, however, in the processes described herein, which are carried out at temperatures from 15 to 80°C or from 25 to 80°C, and preferably at about 15 to 40°C or from 25 to 40°C, there is no need to waste energy by raising the temperature of the eluant prior to eluting the lithium from the adsorbent bed, or by reducing the temperature of the lithium-extract prior to the reverse osmosis or nanofiltration processes.

[0049] As illustrated in Figure 1 , a portion of the lithium-extract 56 may be continuously sent to the first hyperfiltration stage 40 which generates the lithium-rich solution 44 that eventually forms the booster stream 34. The continuous generation of the lithium-rich solution 44 requires a continuous elution of the lithium-extract 54. This may be accomplished by providing the adsorbent bed assembly 20 with multiple adsorption columns, so that at least one of those adsorption columns is producing the lithium-extract 54 during the entire time of the operation of the system 10. Therefore, for the system 10 illustrated in Figure 1 , the lithium-rich solution 44 generation is preferably continuous; however, the presence of the holding tank 50 enables intermittent or continuous booster stream addition to the adsorbent assembly 20. Referring now to Figure 2, a system suitable for intermittent generation

[0050] (using the first hyperfiltration stage 40) and addition of the booster stream (to the adsorbent bed assembly 20) is illustrated. This arrangement is specifically advantageous when the adsorbent bed assembly 20 contains only one column or limited number of columns, such that continuous lithium-extract production is restricted, not practical, or not possible. In those configurations, the system 10 further comprises a liquid storage tank 80 that stores the portion of the lithium-extract 56 until an adequate volume is generated for processing by the first hyperfiltration stage 40.

[0051] The hyperfiltration unit may have a second hyperfiltration stage 60 as depicted in Figure 3. In this case the first hyperfiltration stage produces a lithium-rich intermediate 44’ (comprises the liquid and any dissolved substance(s) present in the liquid that do not pass through or that are rejected by the hyperfiltration (preferably RO) membrane 42) which is fed to the second hyperfiltration stage 60 that houses hyperfiltration membrane 62. In the absence of stage 60, the lithium-rich intermediate 44’ becomes the lithium-rich solution 44.

[0052] The hyperfiltration membrane 62 is preferably a nanofiltration membrane, and a part of the lithium-rich intermediate 44’ passes through it to produce the lithium-rich solution 44. The other part, stream 66, is rejected by the membrane and leaves the hyperfiltration unit and the system 10.

[0053] Nanofiltration membranes selectively pass monovalent ions and reject divalent and multivalent ions (including divalent cations). Therefore, the lithium-rich solution 44 contains a lower concentration of divalent cation than the lithium-rich intermediate 44', and preferably lower than the lithium- extract 54.

[0054] Still referring to Figure 3, the relative position of the first hyperfiltration stage 40 (housing a RO membrane) and the second hyperfiltration stage 60 (housing a NF membrane) can be interchanged. Having a RO membrane in the first stage and a NF membrane in the second stage, as depicted in Figure 3, is advantageous, as an additional high-pressure pump between the two hyperfiltration stages is not required in this configuration. Moreover, the second stage can be of much smaller size as the volume of the lithium-rich intermediate stream 44’ is expected to be much smaller than that of the stream 56, because the stream 44’ is produced through dewatering action in the stage 40. The reverse configuration (second hyperfiltration stage 60 (NF) upstream of the first hyperfiltration stage 40 (RO), not shown) requires a second high pressure pump (as the NF unit permeate is fed to the RO unit) but produces a purer lithium-rich solution 44 as the multivalent ion rejection occurs prior to dewatering.

[0055] The hyperfiltration membrane may be in a flat sheet, hollow-fiber, or tubular configuration, it is preferred that the membrane Is a layered thin-film composite membrane comprising a bottom layer (back side) of a nonwoven backing web (e.g. PET scrim), a middle layer of a porous support having a typical thickness of about 25-125 pm and top layer (front side) comprising a thin film active layer having a thickness typically less than about 1 pm, e.g., from 0.01 pm to 1 pm but more commonly from about 0.01 to 0.1 pm. The porous support provides strength but offers little resistance to fluid flow due to its relatively high porosity. For example, the pore size of the support preferably ranges from about 0.001 to 0.5 pm. Non-limiting examples of porous supports include those made of: polysulfone, polyether sulfone, polyimide, polyamide, polyetherimide, polyacrylonitrile, poly( methyl methacrylate), polyethylene, polypropylene, and various halogenated polymers such as polyvinylidene fluoride. The active layer (top layer) preferably comprises a polymer layer responsible for the desired separation. The active layer polymer may be selected from a group consisting of a fully aromatic polyamide, a semi-aromatic polyamide, a sulfonated polysulfone, a sulfonated poiyethersulfone, and a polysulfonamide. The reverse osmosis membrane active layer polymer may preferably be a fully aromatic polyamide. The active layer polymer may more preferably be a fully aromatic polyamide made by interfacial polymerization of m-phynelenediamine and trimesic acid chloride. The nanofiltration membrane active layer polymer may preferably be a semi-aromatic polyamide. The active layer polymer may more preferably be a semi-aromatic polyamide made by interfacial polymerization of piperazine and trimesic acid chloride. Suitable layered thin-film composite membranes and methods for synthesizing the membranes include those described in U.S. Patent No. 4,277,344, issued to Cadotte, for example. In addition, suitable layered thin-film composite membranes are commercially available from DuPont de Nemours, Inc., of Wilmington, DE, as part of the FilmTec™ brand portfolio of water-separation and purification solutions.

[0056] The lithium-extract may preferably undergo a pH adjustment, a temperature adjustment, or both a pH adjustment and a temperature adjustment before the processing step. The hyperfiltration membranes that comprise a fully aromatic polyamide or a semi-aromatic polyamide are typically recommended for operation at 45 °C or below. At a higher temperature, a combination of high temperature and pressure may lead to membrane compaction, resulting in loss of water permeability (defined as the volume of water passed through a unit membrane area at a given time and applied pressure, which may for example be measured in units of L / (m2*h*bar)). Therefore, if the lithium-extract is an elevated temperature, for example at a temperature above 50 °C, it is preferred to adjust the temperature before subjecting it to the processing step that generates the lithium-rich and the lithium-lean solutions. One possible way to adjust temperature is heat exchange between a hot fluid (here the lithium-extract) and a cold fluid (coolant or water at ambient or sub-ambient temperature) in a heat exchanger. It is also possible to use hyperfiltration membranes (nanofiltration and reverse osmosis) at elevated temperature. For example, FilmTec™ Specialty HTNF and FilmTec™ Specialty HTRO membranes are available for operations with feed temperature up to 70°C. A lithium-extract at elevated temperature can be processed (i.e., without any further temperature adjustment) using a hyperfiltration membrane that is suitable for high temperature operation. Elevated temperature hyperfiltration operation removes the temperature adjustment step and also minimizes energy loss in the form of heat energy. One such operation in lithium extraction has been described in Inti. Appln. No. PCT / CN23 / 140173 by Yang et al., filed on December 20, 2023.

[0057] The manufacturers generally recommend a continuous feed pH range for their hyperfiltration membranes. The recommended pH range is typically from 2 to 11 for a fully-aromatic polyamide reverse osmosis membrane. The pH range is typically from 3 to 10 for a piperazine based semi-aromatic polyamide nanofiltration membrane. These recommended pH values are for long term operation, while a wider pH range (typically from 1 to 13 for reverse osmosis membranes and from 1 to 12 for nanofiltration membranes) can be applied for a short duration (about 30 min.) for cleaning purposes. The use of hyperfiltration membranes for long duration outside of the recommended pH range results in performance loss, which is reflected in an increased ion passage. This performance loss generally arises from hydrolysis of the polyamide active layer under strong alkaline or strong acidic environment. Therefore, if the lithium-extract pH value is outside the recommended hyperfiltration membrane pH range, it is preferred to adjust the pH before advancing to the processing step that generates the lithium-rich and the lithium-lean solutions. For example, if an acidic eluant is used (as is typical for MnCh - based adsorbent), the lithium-extract pH is often less than 2.0, and it is preferred to increase the pH before further processing. pH elevation can be accomplished using a common base such as caustic or lime. Similarly, if the pH of the lithium-extract is too high, a common acid, such as a common mineral acid, for example and without limitation HCI, H2SO4, or H3PO4, can be used to lower the pH to the desired range. The method described herein may have a draining step, a washing step, or a draining and a washing step immediately prior to one or more of the steps in the method. The adsorbent comprises adsorbent particles and the draining step consists of one or more of reducing the quantity (volume or mass) of liquid contained in the interstices between the adsorbent particles, reducing the quantity of liquid contained in the pores of adsorption particles, and reducing the quantity of liquid otherwise bound to the adsorbent.

[0058] In the washing step, the adsorbent bed(s) are washed with suitable washing liquid selected from an aqueous solution of one or more acids, aqueous solution of one or more salts, and an aqueous solution of one or more acids and one or more salts. As illustrated in Figure 4, a washing liquid 72 enters the adsorbent bed assembly 20 and a washed stream 74 leaves the assembly. For superior water management, in some embodiments it may be advantageous to use the lithium-lean solution 46 to form a part of the washing liquid 72. in those cases, stream 47, generated from the lithium- lean solution 46 by regulating a valve 75’ (preferably a three-way ball valve), forms a part of the washing stream 72. The lithium-lean solution 46 is expected to be primarily water (with trace amounts of dissolved species) and it can be mixed with an exogeneous stream 71 to form the washing liquid 72. In the absence of lithium-lean solution recycle loop, for example comprising valve 75’ and stream 47, as depicted in Figure 4, the exogeneous stream 71 becomes the washing liquid 72. The exogeneous stream 71 can be selected from selected from an aqueous solution of one or more acids, aqueous solution of one or more salts, and an aqueous solution of one or more acids and one or more salts.

[0059] The lithium-lean solution recycle loop as described above can similarly be used to form a part of the eluant 52. The lithium-lean solution recycle can be used to generate the washing liquid only, the eluant only, or both the washing liquid and the eluant. Using different valve sets and configurations, dosing can be controlled to obtain the desired composition or ratio of the washing liquid and / or the eluant.

[0060] The drained stream, although not separately depicted, uses the same outlet as the washed stream 74. The drained stream and the washed stream 74 may contain some lithium ions. Specifically, the washed stream 74 may include some desorbed lithium ions, for example if it is sent to the adsorbent bed assembly after the adsorption step(s) and before the desorption step. For superior lithium mass recovery, the washed stream 74 or the drained stream may be used to form a part of the booster stream 34 with or without further processing (also not depicted). A system suitable for generating booster stream 34 using the washed stream 74 is illustrated in Figure 5. A regulating valve 75" is placed in the washed stream flow path to send a portion of the washed stream 74, designated as stream 76, towards the liquid storage tank 80 before further processing. In an alternative embodiment the stream 76 can be sent to the hyperfiltration unit 40 continuously; however, in this configuration, the washed stream volume is preferably low (to minimize the desorbed lithium mass), and storage in the tank 80 is favorable operationally to meet the processing volume demand of the hyperfiltration unit 40.

[0061] The liquid tank 80 can be used to store the stream 56 only, the stream 76 only, the drained stream only, or a mixture of two or more of stream 56, stream 76 and the drained stream.

[0062] In some embodiments, it may be advantageous to run the adsorption bed assembly with one adsorption and one desorption step to achieve operational simplicity. The augmented lithium extraction method described herein is applicable to such a simplified system by directly mixing the booster stream 34 with the portion of the brine stream 14 as illustrated in Figure 6, for example. A portion of the lithium-rich solution 44 is regulated by a valve 70 (preferably a three-way ball valve) to form the booster stream 34. The valve 70 regulates the booster stream dosage or mixing volume ratio of the portion of the brine stream 14 to booster stream 34 to obtain a desired composition of the mixed brine stream 18 entering the adsorption bed assembly 20. In this case both the booster stream 34 and the mixed brine stream 18 have a lithium-ion concentration higher than the lithium-ion concentration of the brine stream 12.The mixing of the booster stream 34 and the portion of the brine stream 14 to produce the mixed brine stream 18 may be performed in a batch, a semi-batch, or a continuous mode. The system and method illustrated in Figure 6 represent a continuous mixing, so long as the regulating valve 70 is fully or partially open to obtain booster stream 34 from the lithium-rich solution 44. Figure 7 illustrates a semi-batch mode of operations (or intermittent mixing) by placing the valve 70 in between the holding tank 50 and the mixing point of the booster stream 34 and the portion of the brine stream 14.

[0063] The following examples are provided to describe the invention in further detail. These examples, which set forth specific embodiments and a preferred mode presently contemplated for carrying out the invention, are intended to illustrate and not to limit the invention.

[0064] EXAMPLES

[0065] Example 1:

[0066] The following procedure was used to determine the composition of a model combined booster stream.

[0067] A 2.5 cm inner diameter column was loaded with 80 mL of a direct lithium extraction (DLE) adsorbent described in U.S. Pat. No. 11 ,371,118. More specifically, the adsorbent was of the formula LiX-2AI(OH)3-nH2O, wherein n was 0 to 10 and X was a halogen. The adsorbent was supported in the pores of a collection of resin beads. The packed column was preheated via recirculated heating fluid in the jacket to 80 °C and filled with enough eluent (water containing 200 mg / L Li, as LiCI) to submerge the adsorbent bed. The column was treated with alternating cycles of brine and then eluant. The brine composition is shown in Table 1 (Brine 1). In each brine half-cycle, the column was treated with 40 bed volumes (BV) of brine at a flowrate of 8 BV / h. The term "bed volume” refers to the volume of the resin, which is 80 mL in this Example. In each eluant half-cycle, the column was treated with 5 BV of eluent at 2 BV / h. These half-cycles were alternated until 7 cycles were completed, and the seventh elute was collected at various time points for analysis. The results of the analysis are shown in Figures 8 and 9. The total quantity of lithium that was eluted from the column during desorption in Cycle 7 is 1 .72 g Li / L sorbent.

[0068] Booster Stream Preparation

[0069] From the desorption profile in Figure 9, the composition of a lithium- extract portion processed to generate the booster stream was determined by combining the fractions that eluted upon treatment with approximately 0.81 to 1 .59 BV of the seventh eluant half-cycle, which is shown in Table 1 as the Li Extract Recycle. When concentrated by a factor of 5, which may be accomplished by techniques such as reverse osmosis or evaporation, e.g., the Lithium Extract Recycle formed the Li Extract Recycle Concentrate, which is the booster stream. Its composition is set forth in Table 1 .

[0070] Table 1. Compositions of liquid streams. The counter anions of this stream are chloride.

[0071] Example 2:

[0072] The following procedure was used to demonstrate the favorable effect of treating the adsorbent column with the model combined booster stream.

[0073] Immediately following the protocol of Example 1 , the temperature of the column was held at 80 °C. The column was then treated with alternating cycles of brine, then the model combined booster stream (Li Extract Recycle Concentrate), and then the eluant. The compositions of the brine, booster stream, and eluant are shown in Table 1. During each brine step, the column was treated with 40 BV of brine at a flowrate of 8 BV / h. During each booster stream step, the column was treated with 0.25 BV of booster stream at 2 BV / h. In each eluant step, the column was treated with 5 BV of eluent at 2 BV / h. These steps were repeated until 7 total additional cycles were completed. Fractions were taken from the final eluate of the seventh cycle, and the analysis of these fractions is shown in Figures 10 and 11. Notably, the total quantity of lithium that was eluted from the column during desorption in Cycle 7 is 3.08 g / L sorbent, which is significantly greater than the amount obtained in Example 1 .

[0074] From the desorption profile in Figure 11 and as shown in Table 1 , various combinations of lithium-extract can be obtained. For example, the combined desorption fractions from 0.80 BV to 5.29 BV are designated Combined Lithium-Extract Product Stream 2, and the combined desorption fractions from 1.22 BV to 5.29BV are designated Combined Lithium-Extract Product Stream 3. The compositions of Combined Lithium-Extract Product Streams 2 and 3 are set forth in Table 1 .

[0075] Combined Lithium-Extract Product Stream 2 is similar to Combined Lithium-Extract Product Stream 1 (generated in Example 1), except that the former includes an additional 0.25 BV of the booster stream (Li Extract Recycle Concentrate) which was added to the column between the adsorption and desorption steps (generated in Example 2). Significantly, the composition of Combined Lithium-Extract Product Stream 2 is higher in lithium and lower in non-lithium cations, compared to Combined Lithium-Extract Product Stream 1 . Likewise, the absolute lithium concentrations of Combined Lithium- Extract Product Streams 1 and 3 are similar; however, the concentration of non-lithium cations is much lower in Combined Lithium-Extract Product Stream 3 compared to Combined Lithium-Extract Product Stream 1 . Thus, Combined Lithium- Extract Product Streams 2 and 3 demonstrate advantageous separation of lithium from a lithium-containing brine, when compared against Combined Product Stream 1.

[0076] Moreover, referring to Figures 9 and 11 , the peak concentration of eluted lithium is significantly higher in Combined Lithium-Extract Product Streams 2 and 3 (about 3750 mg / L, compared to about 1600 mg / L in Combined Lithium- Extract Product Stream 1 ), reflecting the larger quantity of lithium that has been adsorbed onto the column after treatment with the model combined booster stream. Advantageously, this higher peak concentration allows for a more efficient collection of eluted lithium, as a larger amount of lithium is contained in a smaller volume of eluate. Therefore, the results of Examples 1 and 2 demonstrate that not only does the Lithium-Extract of Example 2 yield approximately 80 wt% more lithium compared to that of Example 1 , but also that the purity of the Lithium-Extract is markedly improved in Example 2 and the isolation of the extracted lithium will be more efficient compared to the same for Example 1.

[0077] While certain of the preferred embodiments of the present invention have been described and specifically exemplified above, it is not intended that the invention be limited to such embodiments. Rather, it is to be understood that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.

Claims

CLAIMS:

1. A method of lithium extraction comprising the steps of:(A) providing a brine stream, said brine stream comprising a concentration of dissolved lithium ions and a concentration of dissolved non-lithium cations, said concentrations defining a molar concentration ratio of the dissolved non-lithium cations to the dissolved lithium ions, and wherein the molar concentration ratio is greater than 1 .0;(B) passing a portion of the brine stream through one or more adsorbent bed assemblies, each of said adsorbent bed assemblies comprising at least one adsorbent bed or adsorbent column, and each of said adsorbent bed(s) or adsorbent column(s) comprising an adsorbent; wherein the same adsorbent or two or more different adsorbents are in each bed or column; and wherein lithium ions are extracted from the brine stream onto the adsorbent(s);(C) after passing the portion of the brine stream, passing a portion of a booster stream through at least one of the one or more adsorbent bed assemblies, said booster stream selected from the group consisting of; a) a first booster stream with a lithium-ion concentration higher than the lithium ion concentration of the brine stream, b) a second booster stream wherein the molar concentration ratio of the dissolved non-lithium cations to the dissolved lithium ions is greater than the molar concentration ratio of the dissolved non-lithium cations to the dissolved lithium ions in the brine stream; and c) a combination of the first booster stream and the second booster stream; and(D) passing an eluant through the at least one adsorbent bed assembly to obtain a lithium-extract.

2. The method of claim 1 wherein the concentration of dissolved non- lithium cations in the brine stream is 0.05 mol / L or more.

3. The method of claim 1 or claim 2, wherein said dissolved non-lithium cations comprise one or more ions selected from the group consisting of soluble ions of boron, sodium, potassium, calcium, magnesium, barium, zinc, aluminum, manganese, iron, and strontium.

4. The method of any preceding claim, further comprising a step of processing a portion of the lithium-extract to produce a lithium-rich solution and a lithium-lean solution; said lithium-rich solution having an increased concentration of lithium ions compared to the concentration of lithium ions in the brine stream; and said lithium-lean solution having a decreased concentration of lithium ions compared to the concentration of lithium ions in the brine stream.

5. The method of claim 4, wherein the booster stream comprises a portion of the lithium-rich solution.

6. The method of ciaim 4 or ciaim 5, wherein a portion of the lithium- extract that does not undergo the processing step undergoes treatment via unit operations for one or more of lithium to non-lithium cation separation, lithium-ion concentration, and precipitation of lithium salt(s).

7. The method of any of claims 4 to 6, wherein the processing step is selected from the group consisting of a hyperfiltration step, an ion exchange step, a step of lithium-extraction by solvent, and a combination of two or more steps selected from the group consisting of hyperfiltration step(s), ion exchange step(s), and step(s) of lithium- extraction by solvent.

8. The method of any of claims 4 to 7, wherein each of the lithium-rich solution and the lithium-extract has a divalent cation concentration; and wherein the divalent cation concentration of the lithium-rich solution is higher than the divalent cation concentration of the lithium-extract.

9. The method of any of claims 4 to 7, wherein each of the lithium-rich solution and the lithium-extract has a divalent cation concentration; and wherein the divalent cation concentration of the lithium-rich solution is lower than the divalent cation concentration of the lithium-extract.

10. The method of any of claims 4 to 9, wherein the lithium-extract undergoes a pH adjustment, a temperature adjustment, or both a pH adjustment and a temperature adjustment before the processing step.11 . The method of any preceding claim, wherein the molar concentration ratio of the dissolved non-lithium cations to the dissolved lithium ions in the lithium-extract is less than the molar concentration ratio of the dissolved non-lithium cations to the dissolved lithium ions in the brine stream.

12. The method of any preceding claim, wherein the portion of the brine stream is passed through an apparatus, said apparatus comprising the at least one adsorbent bed assembly, said apparatus selected from a system comprising one or more adsorbent bed assemblies that are arranged in parallel, in series, or in a configuration comprising adsorbent bed assemblies arranged in parallel and adsorbent bed assemblies arranged in series; and wherein each of said one or more adsorbent bed(s) or adsorbent column(s) is independently selected from the group consisting of a fixed bed, a packed bed, a continuous countercurrent adsorption / desorption system, a continuous countercurrent ion exchange system, a simulated moving bed column system, a moving bed column system such as a Higgins loop, a continually stirred adsorption tank, and a continually stirred ion exchange tank.

13. The method of any preceding claim, wherein the adsorbent comprises a lithium selective adsorbent.

14. The method of any preceding claim wherein said adsorbent comprises one or more of a lithium aluminum intercalate, a lithium aluminum layered double hydroxide chloride, a layered double hydroxide modified activated alumina, a layered double hydroxide modified activated boehmite, a layered double hydroxide loaded or synthesized within an ion exchange resin or copolymer or molecular sieve or zeolite or porous material, a blend of lithium aluminum intercalates with polymers, a manganese oxide, a manganese oxide that has been blended with at least one polymer, a titanium oxide, a titanium oxide that has been blended with at least one polymer, and an immobilized crown ether.

15. The method of any preceding claim, wherein the adsorbent further comprises a polymer.

16. The method of claim 15, wherein said polymer is selected from the group consisting of polystyrene, polyacrylic acid, polymethylmethacrylate, polyacrylamide, polyvinylidene fluoride, polyvinyl fluoride, polyvinylchloride, polyvinyl alcohol, polytetrafluoroethylene, and related polymers.

17. The method of any preceding claim, wherein the eluant comprises an aqueous solution selected from the group consisting of a dilute solution comprising a halide salt, a dilute solution comprising a non-halide salt, an acidic solution, a buffer solution, and a combination of two or more of a dilute solution comprising a halide salt, a dilute solution comprising a non-halide salt, an acidic solution, and a buffer solution.

18. The method of any preceding claim, wherein the temperature of the eluant is from 15 to 120°C.

19. The method of any preceding claim, further comprising one or more washing steps between steps (B) and (C), between steps (C) and (D), or between steps (B) and (C) and between steps (C) and (D), wherein the adsorbent bed or column is drained of liquid prior to starting thenext step and optionally wherein a washed stream leaves the adsorbent bed assemblies.

20. The method of any preceding claim wherein the adsorbent bed is drained of liquid immediately prior to one or more of steps (A), (B), (C), or (D); in which the adsorbent comprises adsorbent particles; and in which draining consists of one or more of reducing the quantity of liquid contained in the interstices between the adsorbent particles, reducing the quantity of liquid contained in the pores of the adsorption, and reducing the quantity of liquid otherwise bound within the adsorbent material; and optionally wherein a drained stream leaves the adsorbent bed assemblies.

21. The method of any preceding claim, wherein the adsorbent bed(s) are washed with a suitable washing liquid immediately prior to one or more of steps (A), (B), (C), or (D), and the suitable washing liquid is selected from an aqueous solution of one or more acids, an aqueous solution of one or more salts, and an aqueous solution of one or more acids and one or more salts.

22. The method of any preceding claim, wherein the washed stream or the drained stream forms a part of the booster stream with or without any further processing.

23. The method of any of claims 4 through 22, wherein the processing step uses at least one hyperfiltration unit; wherein said unit comprises at least one pump fluidly connected to at least one hyperfiltration stage; and wherein said hyperfiltration stage comprises a hyperfiltration membrane.

24. The method of any of claims 4 through 23, wherein the hyperfiltration membrane comprises a polymer layer selected from the group consisting of a fully aromatic polyamide, a semi-aromatic polyamide, a sulfonated polysulfone, a sulfonated polyethersulfone, and a polysulfonamide.

25. The method of any of claims 4 through 24, wherein the hyperfiltration unit operates in a batch, a semi-batch, or a continuous mode.

26. The method of any preceding claim, wherein the booster stream comprises a portion of the brine stream.

27. A method of lithium extraction comprising the steps of:(A) providing a brine stream, said brine stream comprising a concentration of dissolved lithium ions and a concentration of dissolved non-lithium cations, said concentrations defining a molar concentration ratio of the dissolved non-lithium cations to the dissolved lithium ions, and wherein the molar concentration ratio is greater than 1 .0;(B) providing a booster stream selected from the group consisting of a) a first booster stream with a lithium-ion molar concentration higher than the lithium-ion molar concentration in the brine stream; b) a second stream having a molar concentration of dissolved lithium ions and a molar concentration of dissolved non-lithium cations, wherein the molar concentration ratio of the dissolved non-lithium cations to the dissolved lithium ions is greater than the molar concentration ratio of the brine stream; and c) a combination of the first booster stream and the second booster stream;(C) mixing a portion of the brine stream with a portion of the booster stream to create a mixed stream;(D) passing a portion of the mixed stream through an adsorbent bed to extract the lithium ions from the mixed stream onto an adsorbent; and(E) passing an eluant through the adsorbent bed to obtain a lithium- extract.

28. The method of claim 27, wherein the molar concentration ratio of the lithium-extract is lower than the molar concentration ratio of the brine stream.

29. The method of claim 27 or claim 28, wherein the brine stream and the booster stream mixing are performed in a batch, a semi-batch, or a continuous mode.

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