A novel integrated pretreatment and protein-tethered bead separation system for energy critical element (ECE) recovery from ECE-enriched water sources

Abstract

A method for recovering a rare earth element (REE) from an REE enriched feed. The method includes removing at least a portion of a non-REE component from the REE enriched feed to produce a pretreated feed, feeding the pretreated feed through a non-REE component separation unit to produce a first REE extract, and recovering the REE from the first REE extract in an REE separation unit. A system for recovering a rare earth element (REE) from an REE enriched feed includes a pretreatment unit configured to pretreat the REE enriched feed and produce a pretreated feed, a non-REE separation unit configured to produce a first REE extract, and an REE separation unit configured to recover the REE from the first REE extract.

Description

PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOl A NOVEL INTEGRATED PRETREATMENT AND PROTEIN-TETHERED BEAD SEPARATION SYSTEM FOR ENERGY CRITICAL ELEMENT(ECE) RECOVERY FROM ECE-ENRICHED WATER SOURCES BACKGROUND

[0001] Rare Earth Elements (REEs) are critical components in a wide array of advanced technologies, including sensors, batteries, magnets, and computing devices. REEs also play a pivotal role in renewable energy production and distribution. Despite their name, REEs are not rare but are typically found in low concentrations within ore deposits across the globe. However, isolating REEs remains a challenge as extracting and purifying REEs is far more energy- and chemically-intensive than the extraction and isolation processing required for other metals. These challenges, coupled with market dynamics, make the recovery of rare earths from mineral sources particularly complex for many nations. Accordingly, there exists a need for methods for the extraction and concentration of REEs from complex mixtures.SUMMARY

[0002] This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.

[0003] In one aspect, embodiments disclosed herein relate to a method for recovering a rare earth element (REE) from an REE enriched feed. The method includes removing at least a portion of a non-REE component from the REE enriched feed to produce a pretreated feed, feeding the pretreated feed through a non-REE component separation unit to produce a first REE extract, and recovering the REE from the first REE extract in an REE separation unit.

[0004] In another aspect, embodiments disclosed herein relate to a system for recovering a rare earth element (REE) from an REE enriched feed. The system includes a pretreatment unit configured to pretreat the REE enriched feed and produce a pretreated feed, a non-PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlREE separation unit configured to produce a first REE extract, and an REE separation unit configured to recover the REE from the first REE extract.

[0005] Other aspects and advantages of the claimed subject matter will be apparent from the following description and the appended claims.BRIEF DESCRIPTION OF DRAWINGS

[0006] FIG. 1 is a simplified diagram of an REE recovery system in accordance with one or more embodiments.

[0007] FIG. 2 is a simplified diagram of an REE recovery system in accordance with one or more embodiments.

[0008] FIG. 3 is a simplified diagram of a computer system in accordance with one or more embodiments.

[0009] FIG. 4 is a block flow diagram of a method for recovery REEs in accordance with one or more embodiments.

[0010] FIG. 5 is a simplified process flow diagram used for an exemplary REE recovery process in accordance with one or more embodiments.

[0011] FIG. 6A is a graph showing number of Bed Volumes versus the loading (C / Co) of REEs adsorbed in an aluminum (Al) specific column.

[0012] FIG. 6B is a graph showing number of Bed Volumes versus the loading (C / Co)of non-REE components adsorbed in an Al specific column.

[0013] FIG. 7A is a graph showing number of Bed Volumes versus the concentration in parts per million (ppm) of REEs present in a strip solution.

[0014] FIG. 7B is a graph showing number of Bed Volumes versus the concentration in ppm of non-REE components present in a strip solution from an Al-specific column.

[0015] FIG. 8A is a graph showing number of Bed Volumes versus the loading (C / Co) of REEs adsorbed in an REE-selective column from an Al-specific column.PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOl

[0016] FIG. 8B is a graph showing number of Bed Volumes versus the loading (C / Co) of non-REE components adsorbed in an REE-selective column.

[0017] FIG. 9A is a graph showing number of Bed Volumes versus the concentration in ppm of REEs present in a strip solution from an REE-selective column.

[0018] FIG. 9B is a graph showing number of Bed Volumes versus the concentration in ppm of non-REE components present in a strip solution from an REE-selective column.DETAILED DESCRIPTION

[0019] The demand for REEs, such as lanthanide elements, germanium, yttrium, scandium, and gallium, continues to rise as the global economy moves toward electrification, decarbonization, and the advancement of sophisticated computing. However, in regions like the Americas and Europe, the industrial-scale recovery and purification of REEs remain underdeveloped largely as a result of the significant environmental impact that would result from traditional separation and purification processes for recovering REEs. As a result, China currently controls over 90% of the global supply chain of REEs.

[0020] Both government initiatives and private industry investments are now accelerating efforts to establish domestic REE supply chains, particularly with the growth of renewable energy technologies and the electronics markets. Historically, meeting this demand would have focused on identifying and developing new virgin REE deposits, which is a process that can take decades. However, recent attention has turned to enhancing recovery from existing resources, such as REE enriched wastewater streams.

[0021] Traditionally, the recovery of REEs from REE enriched wastewater, such as mine- impacted water and / or coal ash leachate, presents its own set of challenges. These water sources often contain extremely high relative concentrations of non-REE metals like aluminum, calcium, magnesium, and iron present in amounts that are typically thousands of times greater than the REE content. This abundance of competing metals complicates traditional purification processes and has been a persistent barrier to efficient REE recovery. Additionally, traditional separation processes are generally limited by theirPATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlability to recover REEs from sources having relatively low REE concentrations. For example, traditional processes generally have difficulty in recovering REEs from solutions having low concentrations (e.g.,500 parts per million (ppm) or less, such as less than 100 ppm) of REEs. Thus, conventional extraction technologies are often limited to extraction of target elements from liquids obtained from ore materials, such as mining tailings and / or electronic waste (e.g., spent electronic waste), as the concentration of REEs in these liquids obtained are often in the range of gram(s) per liter (i.e., above 1000 ppm).

[0022] As such, due to the complexity of the competing elements in REE enriched sources as well as concentration limitations of traditional processes, there remains a need for development of extraction of REEs from REE enriched sources, like mine impacted water and / or coal ash leachate.

[0023] Embodiments herein are directed toward technologies that enhance recovery from existing resources, including REE-enriched wastewater streams, such as mine-impacted water, coal ash leachate, or combinations thereof. The technologies (i.e., systems and processes) described herein advantageously address technical challenges associated with traditional REE recovery and offer a more rapid and sustainable alternative to mining virgin resources, thereby mitigating the significant environmental costs associated with traditional extraction methods. A system and method of one or more embodiments may generally include a pretreatment step and selective capture of an REE from a water source. One or more embodiments herein are directed to systems and method that leverage the element-specific selectivity of metal-binding proteins to enable the efficient capture and purification of REEs from dilute water streams, such as dilute wastewater streams. Embodiments disclosed herein advantageously utilize biological processes that govern metal acquisition, transport, and sequestration to develop environmentally sustainable technologies for REE mining and manufacturing applications.

[0024] REE RECOVERY SYSTEM

[0025] In one aspect, embodiments herein relate to a system for recovering an REE from an REE enriched feed. The REE enriched feed may include an REE enriched water, such as mine- impacted water, acid mine drainage, coal ash leachate, or combinations thereof. InPATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlsome embodiments, the REE enriched feed can include a wastewater (e.g., obtained from a mining process, a natural wastewater including but not limited to acid mine drainage, coal mine drainage, or other mine impacted water), an active leachate of coal ash and / or fly ash, or any combination thereof. In some embodiments, the REE enriched feed can includes processed water from various industries. The phrase “REE enriched feed” refers to a water that includes metals, such as transition metals, heavy metals, energy critical elements (e.g., a metal used in energy applications such as REEs, including, but not limited to, a lanthanide REE such as one lanthanide REEs or a plurality of lanthanide REEs, germanium, yttrium, scandium, and / or gallium), among other components.

[0026] As used herein, the phrase “mine-impacted water” refers to a water produced during mining and / or metallurgical activities, originate from abandoned mines, or a water including combinations thereof. In some embodiments, mine-impacted water can include acid mine drainage, acid rock drainage, or combinations thereof. Acid rock drainage may be naturally present as a result of a weathering process a of natural rock and / or may occur as a result of artificial disturbances to the earth (e.g., due to mining and / or other large-scale construction activities). In some embodiments, acid rock drainage can be obtained from an acidic liquid that drains from coal stocks, coal handling facilities, coal washeries, and / or coal waste tips.

[0027] The phrase “coal ash leachate” refers to an acidic liquid obtained from a coal ash leaching process. As used herein, the term “leach” refers to the process of transferring one or more components from a first material (e.g., a solid derived from coal ash) to a second material (e.g., a liquid lixiviant). For example, the process of “leaching” may include transferring one or more components from a solid derived from coal ash to an acidic liquid in accordance with one or more embodiments. As a non-limiting example, a coal ash is directly subjected to an acidic leaching process (without prior pretreatment) in one or more embodiments such that the acidic liquid formed after the leaching of the coal ash and containing at least one component from the coal ash is considered a “coal ash leachate.” The acidic leaching process may include using an inorganic acid including, but not limited to, sulfuric acid, hydrochloric acid, and nitric acid in the liquid lixiviant.PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOl

[0028] In one or more embodiments, a “coal ash leachate” is a liquid formed when coal ash is first treated with a basic solution (e.g., a sodium hydroxide solution). The hydroxide solution removes a non-REE component from the coal ash to provide solids (e.g., a precipitate) derived from coal ash and a hydroxide solution including the non-REE component. The solids derived from coal ash are then collected after the basic treatment and subsequently leached in an inorganic acid including, but not limited to, sulfuric acid, hydrochloric acid, and nitric acid. As one of ordinary skill may appreciate, the coal ash leachate may be formed in and recovered from a reactor (e.g., a continuous stirred tank reactor) as a pretreatment in one or more embodiments. The acidic liquid containing at least one component from the coal ash is referred to herein as a “coal ash leachate.”

[0029] The REE enriched feed may be an acidic fluid. A pH of the REE enriched fluid may be in a range from about 0.01 to about 4.5. For example, a pH of the REE enriched fluid may be in a range having a lower limit of any one of 0.01, 0.05, 0.10, 0.25, 0.50, 0.75, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.75, 1.9, 2.0, 2.1, 2.2, 2.5, 2.75, 2.9, and 3.0 and an upper limit of any one of 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.75, 1.9, 2.0, 2.1, 2.25, 2.5, 2.75, 2.9, 3.0, 3.1, 3.25, 3.5, 3.75, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, and 4.5, where any lower limit can be paired with any mathematically compatible upper limit.

[0030] The REE enriched feed may include at least one REE. The REE may be selected from the group consisting of neodymium, lanthanum, terbium, dysprosium, ytterbium, samarium, praseodymium, promethium, europium, gadolinium, lutetium, holmium, erbium, thulium, gallium, germanium, yttrium, scandium, and combinations thereof. While capable of recovering an REE from a solution having an REE concentration of above 750 ppm, the system (and method) described herein may advantageously be capable of recovering an REE from a feed having a relatively low concentration of REEs (e.g., below 500 ppm or even as low as below 100 ppm, such as 0.5 ppm) as compared to a traditional system used for REE recovery.

[0031] In one or more embodiments, the REE enriched feed has a concentration of at least one REE of 750 ppm or less, such as 700 ppm or less, 650 ppm or less, 600 ppm or less, 575 ppm or less, 550 ppm or less, 525 ppm or less, 510 ppm or less, 500 ppm or less, 490PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlppm or less, 475 ppm or less, 450 ppm or less, 425 ppm or less, 400 ppm or less, 350 ppm or less, 300 ppm or less, 250 ppm or less, 200 ppm or less, 175 ppm or less, 150 ppm or less, 125 ppm or less, 100 ppm or less, 75 ppm or less, 50 ppm or less, 25 ppm or less, 10 ppm or less, 5 ppm or less, or 1 ppm or less.

[0032] In some embodiments, the REE enriched feed has a concentration of at least one REE of 0.4 ppm or more, 0.5 ppm or more, 1 ppm or more, 5 ppm or more, 10 ppm or more, 25 ppm or more, 50 ppm or more, 75 ppm or more, 100 ppm or more, 125 ppm or more, 150 ppm or more, 175 ppm or more, 200 ppm or more, 250 ppm or more, 300 ppm or more, 350 or more, 400 ppm or more, 425 ppm or more, 450 ppm or more, 475 ppm or more, 490 ppm or more, 500 ppm or more, 510 ppm or more, 525 ppm or more, 550 ppm or more, 575 ppm or more, 600 ppm or more, 650 ppm or more, 700 ppm or more, or 750 ppm or more. As a non-limiting example, an REE enriched feed may have a concentration of at least one REE of 0.4 ppm or more and less than 5 ppm, such as approximately 0.5 ppm of at least one REE.

[0033] In some embodiments, the REE enriched feed has a concentration of at least one REE in a range having a lower limit of any one of 0.4, 0.5, 1, 5, 10, 25, 50, 75, 100, 125, 150, 175, 200, 250, 300, 350, 400, 425, 450, 475, 490, 500, 510, 525, 550, 575, 600, 650, and 700 ppm and an upper limit of any one of 0.75, 1, 5, 10, 25, 50, 75, 100, 125, 150, 175, 200, 250, 300, 350, 400, 425, 450, 475, 490, 500, 510, 525, 550, 575, 600, 650, 700, and 750 ppm, where any lower limit may be paired with any mathematically compatible upper limit.

[0034] In one or more embodiments, the REE enriched feed has a total concentration of REEs of 750 ppm or less, such as 700 ppm or less, 650 ppm or less, 600 ppm or less, 575 ppm or less, 550 ppm or less, 525 ppm or less, 510 ppm or less, 500 ppm or less, 490 ppm or less, 475 ppm or less, 450 ppm or less, 425 ppm or less, 400 ppm or less, 350 ppm or less, 300 ppm or less, 250 ppm or less, 200 ppm or less, 175 ppm or less, 150 ppm or less, 125 ppm or less, 100 ppm or less, 75 ppm or less, 50 ppm or less, 25 ppm or less, 10 ppm or less, 5 ppm or less, or 1 ppm or less.PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOl

[0035] In some embodiments, the REE enriched feed has a total concentration of REEs of 0.4 ppm or more, 0.5 ppm or more, 1 ppm or more, 5 ppm or more, 10 ppm or more, 25 ppm or more, 50 ppm or more, 75 ppm or more, 100 ppm or more, 125 ppm or more, 150 ppm or more, 175 ppm or more, 200 ppm or more, 250 ppm or more, 300 ppm or more, 350 or more, 400 ppm or more, 425 ppm or more, 450 ppm or more, 475 ppm or more, 490 ppm or more, 500 ppm or more, 510 ppm or more, 525 ppm or more, 550 ppm or more, 575 ppm or more, 600 ppm or more, 650 ppm or more, 700 ppm or more, or 750 ppm or more. As a non-limiting example, an REE enriched feed may have a total concentration of REEs of 0.4 ppm or more and less than 5 ppm, such as approximately 0.5 ppm of a total concentration of REEs. As one of ordinary skill may appreciate, coal ash may include a concentration of approximately 2000 ppm or more in the solid material. Thus, a coal ash leachate of one or more embodiments can include a total concentration of REEs above 750 ppm, such as 1000 ppm or more, 1500 ppm or more, or 2000 ppm or more.

[0036] In some embodiments, the REE enriched feed has a total concentration of REEs in a range having a lower limit of any one of 0.4, 0.5, 1, 5, 10, 25, 50, 75, 100, 125, 150, 175, 200, 250, 300, 350, 400, 425, 450, 475, 490, 500, 510, 525, 550, 575, 600, 650, and 700 ppm and an upper limit of any one of 0.75, 1, 5, 10, 25, 50, 75, 100, 125, 150, 175, 200, 250, 300, 350, 400, 425, 450, 475, 490, 500, 510, 525, 550, 575, 600, 650, 700, and 750 ppm, where any lower limit may be paired with any mathematically compatible upper limit.

[0037] The system may include a pretreatment unit and an REE capturing unit. A system 100 in accordance with one or more embodiments may include a pretreatment unit 102 and an REE capture unit 104 as shown in FIG. 1. The system of one or more embodiments may be configured for laboratory experiments (e.g., benchtop experiments), for a larger scale setting such as in an industrial setting, or combinations thereof. As one of ordinary skill may appreciate, system 100 in accordance with one or more embodiments may include various sensors (e.g., temperature, pressure, pH, among others), pumps, flow control valves, among other components known in the art.

[0038] The system 100 of one or more embodiments may be configured to separate an REE from a feed that includes a complex mixture of components. The REE enriched feedPATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlmay include mine-impacted water that may be recovered from a formation, may be recovered from a waste material of a drilling and / or mining operation, or any combination thereof. In one or more embodiments, the REE enriched feed includes a coal ash leachate. In one or more embodiments, the REE enriched feed includes one REE or a plurality of REEs (e.g., a mixture of two or more REEs, three or more REEs, four or more REEs, five or more REEs, six or more REEs, etc.). The REE enriched feed may include an REE as a relatively minor component and a non-REE component as a major component. The nonREE component may include non-REE salts, non-REE metals, organic molecules, or any combination thereof.

[0039] The REE enriched feed may be introduced to pretreatment unit 102 via feed line 101. The pretreatment unit 102 of system 100 may be configured to adjust the pH of the REE enriched feed. In one or more embodiments, the pretreatment unit 102 is configured to adjust the pH of the REE enriched feed to increase the basicity of the feed and produce a pretreated feed having a pH higher than the REE enriched feed. In one or more embodiments, increasing the basicity of the REE enriched feed promotes the precipitation of a non-REE component (e.g., a non-REE metal including, but not limited to Fe and / or Al) from the REE enriched feed to produce a pretreated feed. Pretreatment unit 102 may be capable of separating the pretreated feed from the precipitate. As such, the system of one or more embodiments is capable of first reducing a concentration of the non-REE components via pretreatment unit 102 that is capable of increasing a pH of the REE enriched feed.

[0040] As a non-limiting example, in a system configured to be present in a laboratory setting, pretreatment unit 102 may include a glass beaker. Alternatively, in a system configured to be present in an industrial setting, pretreatment unit 102 can include an industrial scale mixing unit The pretreatment unit 102 of one or more embodiments is capable of receiving a pH adjusting agent, which may be as known by those of ordinary skilled in the art, to provide a pretreated fluid having a pH higher than a pH of the REE enriched fluid. The pH of the pretreated fluid may be predetermined prior to pretreatment.PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOl

[0041] For example, the pH adjusting agent may include, a buffer, a base, or any combination thereof. In some embodiments, where a pretreated fluid has a predetermined pH, an acid may be added to pretreatment unit 102 as a component of the pH adjusting agent such that the acid assists in achieving the predetermined pH of the pretreated fluid. Pretreatment unit 102 may include one or more material transport lines in fluid and / or solid communication with a pH adjusting agent source (not shown in FIG. 1). Pretreatment unit 102 may be in electrical communication with a control unit (not shown in FIG. 1) such that the transport of a pH adjusting agent, an REE enriched feed, or any combination thereof can be controlled by a control unit. In some embodiments, pretreatment unit 102 is manually controlled such that the addition of an REE enriched feed, a pH adjusting agent, an optional chelating agent, or any combination thereof is manually controlled by an operator. The chelating agent may selectively target a non-REE component for removal from the feed. The chelating agent may target an REE component to keep the REE in the pretreated fluid while non-REE component(s) are precipitated.

[0042] Pretreatment unit 102 may be configured to precipitate at least a portion of a non- REE component (or an impurity), such as a non-REE metal, from the REE enriched feed to produce a pretreated fluid. Pretreatment unit 102 may include one or more components known to those skilled in the art to separate a precipitate that can include at least one non- REE component (e.g., Al and / or Fe) from a liquid, such as via decantation, gravity filtration, centrifugation, membrane filtration, among other separation techniques. In some embodiments, pretreatment unit 102 is configured such that an operator is capable of removing the precipitate from the pretreated fluid via fluid transport line 103. Pretreatment unit 102 may include at least one chromatography column to separate non-REE components from the pretreated fluid to produce a first extract.

[0043] A pH of the pretreated fluid (e.g., produced by pretreatment unit 102) may be in a range from 3.0 to 5.5. For example, a pH of the pretreated fluid may be in a range having a lower limit of any one of 3.0, 3.25, 3.5, 3.75, 3.9, 4.0, 4.1, 4.2, 4.25, 4.3, 4.4, 4.5, 4.6, 4.7, 4.75, 4.8, 4.9, and 5.0 and an upper limit of any one of 4.0, 4.1, 4.2, 4.25, 4.3, 4.4, 4.5, 4.6, 4.7, 4.75, 4.8, 4.9, 4.95, 5.0, 5.1, 5.2, 5.3, 5.4, and 5.5, where any lower limit can be paired with any mathematically compatible upper limit.PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOl

[0044] In one or more embodiments, the untreated REE enriched feed, the pretreated fluid, or both includes non-REE metals in an amount higher than an amount of an REE present in solution. The untreated REE enriched feed may have a concentration of non-REE components, such as non-REE metals, that is higher than the pretreated feed. In some embodiments, the difference in REE concentration of the REE enriched feed and the pretreated feed is minimal or non-existent.

[0045] In some embodiments, the system 100 includes a non-REE separation unit (not shown in FIG. 1). The non-REE separation unit may be integrated into pretreatement unit 102, REE capture unit 104, or can be a standalone unit. The non-REE separation unit may include at least one chromatography column selective for a non-REE component such that the non-REE component is retained on a stationary phase of the at least one chromatography column. In one or more embodiments, the stationary phase is non- selective for an REE. The stationary phase may include non-functionalized adsorbing material, including, but not limited to, silica beads. The non-REE separation unit may be in fluid communication with pretreatment unit 102 and REE capture unit 104.

[0046] REE capture unit 104 may be capable of receiving the pretreated feed via one or more fluid transport lines 103, operator transport (e.g., via manual introduction), or any combination thereof. REE capture unit 104 may be configured to perform at least one chromatographic separation. REE capture unit 104 may include an optional non-REE separation unit and an REE separation unit (not shown in FIG. 1).

[0047] A simplified system 200 in accordance with one or more embodiments may be as shown in FIG. 2. System 200 includes pretreatment unit 202. Pretreatment unit 202 may be as described previously (e.g., as described in pretreatment unit 102 in FIG. 1). System 200 includes REE capture unit 204. The REE capture unit may optionally include a first unit that is configured to further reduce a non-REE component from the pretreated fluid. As shown in FIG. 2, non-REE separation unit 205 may be a separate unit from the REE capture unit 204. Non-REE separation unit 205 may be downstream of pretreatment unit 202. In some embodiments, while not shown in FIG. 2, it may be appreciated that non- REE separation unit 205 is located within pretreatment unit 202 and downstream of aPATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlprecipitation zone. The precipitation zone of pretreatment unit 202 may be configured to precipitate a non-REE component from the REE enriched feed such that a treated fluid is produced and transferred to the non-REE separation unit. In some embodiments, non-REE separation unit 205 is in fluid communication with an outlet of pretreatment unit 202 such that non-REE separation unit 205 is capable of receiving a pretreated fluid 201A from a precipitation zone (e.g., a vessel) of pretreatment unit 202.

[0048] In FIG. 2, fluids and their respective directions are labelled as with arrows 201 A to 20 IK. One or more fluids may be collected and / or transferred via manual operation. Alternatively, one of ordinary skill may appreciate that these arrows 201 A to 20 IK can include fluid transport lines such that one or more components of the system 200 are in fluid communication with one or more subsequent components. Such fluid transport lines may include one or more selected from pumps, valves, flow control equipment, sensors, among other components.

[0049] In FIG. 2, non-REE separation unit 205 is upstream of and in fluid communication with one or more REE separation units (e.g., unit 208 and optional unit 210) of the REE capture unit. Non-REE separation unit 205 may include one or more chromatography columns. The chromatography columns of one or more embodiments may include an adsorbing material (e.g., a solid phase) capable of selectively separating one or more components from a mixture. The one or more chromatography columns of the non-REE separation unit 205 may include an adsorbing material that is selective for non-REE components in a pretreated fluid. As a non-limiting example, an adsorbing material of the one or more chromatography columns of non-REE separation unit 205 may be selective for non-REE components such that the adsorbing material is capable of selectively trapping the non-REE components from the pretreated fluid to form a first extract containing the REE. The non-REE components present in a pretreated feed may include, but are not limited to, organic components, non-REE salts, transition metals (including, but not limited to, aluminum, iron, magnesium, calcium, among others). In one or more embodiments, the adsorbing material of the one or more chromatography columns of the non-REE separation unit 205 includes silica beads.PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOl

[0050] Non-REE separation unit 205 may receive a wash solution 201B from a first wash solution source 206. As used herein, the term “wash solution” refers to a solution that disrupts the binding of an atom and / or molecule from the adsorbing material of a chromatography column such that the atom and / or molecule is included in an eluent. In some embodiments, one or more chromatography columns can be regenerated for a subsequent separation via application of a wash solution.

[0051] The first wash solution 20 IB may be configured to regenerate the one or more chromatography columns of the non-REE separation unit 205. The first wash solution may include a component that removes non-REE components withheld on the one or more chromatography columns of the non-REE separation unit 205 to regenerate one or more chromatography columns of the non-REE separation unit 205. The non-REEs captured in the non-REE separation unit 205 may be recovered in non-REE extract 201C such that the REE is substantially absent from extract 201 C.

[0052] Non-REE separation unit 205 may be configured to produce a first REE extract 201D. The first REE extract may include an REE, a reduced concentration of a non-REE impurity component as compared to a pretreated fluid, and combinations thereof. The first REE extract 20 ID may have a reduced concentration of non-REE components as compared to the pretreated feed. A pH of the first REE extract 20 ID may approximately be the same pH as the pretreated feed.

[0053] The first REE extract 20 ID may be passed through at least one REE separation unit. The REE separation unit may include at least one REE selective column, such as a first REE selective column 208 and one or more optional additional REE selective columns (represented by column 210 in FIG. 2). The one or more optional additional REE selective columns may be arranged in parallel or in a series. Each of the one or more optional additional REE selective columns may include an absorbing material that is the same or different from the first REE selective column 208. For example, a system may include multiple REE selective columns that can each include a different REE binding component for the purpose of recovering and purifying multiple different REEs. In some embodiments, an adsorbing material of a single REE selective column can include different REE bindingPATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlcomponents (i.e., proteins and / or small molecules) for the purpose of recovering and purifying multiple different REEs. The REE binding component of one or more embodiments may be selective for a lanthanide REE, germanium, yttrium, scandium, and / or gallium.

[0054] The first REE selective column 208, the optional additional REE selective column 210, or both are configured to separate an REE from solution via column chromatography. First REE selective column 208 may include a stationary phase adsorbing material that is selective for an REE such that a second extract 20 IE has a reduced REE concentration as compared to the first extract 201D. In one or more embodiments, an REE is substantially absent from second extract 20 IE. The adsorbing material of the REE selective column may include, but is not limited to, REE selective proteins, REE selective compound, a solid phase support, or any combination thereof such that an REE is trapped (or bound) to the adsorbing material of the first REE separation column 208. The REE selective protein, REE selective compound, or both may be natural or synthetically engineered (e.g., with synthetic biology, synthetic chemistry, or both). The REE selective protein may include, but is not limited to, Lanmodulin (LanM) and / or variants of LanM. The variants of LanM may be produced via synthetic biology. As a non-limiting example, the adsorbing material of the first REE selective column 208 may include LanM functionalized silica beads, silica beads functionalized with variants of LanM, or any combination thereof.

[0055] A second wash solution 20 IF may be applied to the first REE selective column 208 from a second wash solution source 212 to remove non-REE impurities from column 208, recover REEs bound to the adsorbing material of column 208, or any combination thereof. The second wash solution may include a dilute acidic solution (e.g., hydrochloric acid), an REE chelator, or any combination thereof. Non-REE impurities recovered from column 208, REEs bound to the adsorbing material of column 208, or any combination thereof may be recovered in a third extract 201 G after rinsing the column with the second wash solution. In one or more embodiments, non-REE components are substantially absent from third extract 201 G such that the third extract 201G is an REE retentate.PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOl

[0056] In some embodiments, at least a portion of the first extract (represented by 201 H in FIG. 2), at least a portion of the third extract (not shown in FIG. 2), or combinations thereof are fed through an optional additional REE selective column 210 to produce a fourth extract 2011. The adsorbing material of the first REE selective column 208 and the adsorbing material of the optional additional REE selective column 210 may be selective for the same REE, different REEs, or combinations thereof. The adsorbing material of the optional additional REE selective column 210 may include REE selective proteins, REE selective small molecules, a solid-phase support, or any combination thereof such that an REE is bound to the adsorbing material. The REE selective protein, REE selective small molecule, a solid-phase support, or any combination thereof may be as described previously. As a non-limiting example, the optional additional REE selective column may include silica beads functionalized with LanM and / or a LanM variant functionalized silica beads.

[0057] In embodiments where at least one optional additional column 210 are present in system 200, at least a portion of the second wash solution 201 J may be introduced to column 210 to recover an REE, remove impurities, or any combination thereof in a fifth extract 20 IK. In one or more embodiments, non-REE components are absent from the fifth extract 20 IK. The second wash solution may include one or more components to disrupt the binding of the REE from the REE selective molecule of the adsorbing material such that the REE is included in the third extract 201G and / or the fifth extract 201K. In one or more embodiments, the REE is the major component of the third extract 201 G and / or the fifth extract 20 IK.

[0058] Referring back to FIG. 1, the pretreatment unit 102, the REE capture unit 104, or combinations thereof are optionally in electric connection with a control system 106. The control system 106 may be configured to control the flow of feed to be treated in the pretreatment unit 102, control the flow of a pretreated fluid from pretreatment unit 102 through REE capture unit 104, or any combination thereof. In one or more embodiments REE capture unit 104 is in electrical communication with a control unit such that the pretreated feed may be transported from the pretreatment unit 102 automatically. The control unit may be configured to operate a rate of flow through the REE capture unit 104, such that REE can be recovered from the pretreated fluid.PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOl

[0059] A system in accordance with one or more embodiments may include a control system (e.g., optional control system 106 shown in FIG. 1 ) that includes a computer system. The computer system, control system, or both may be in electrical connection with the pretreatment unit 102 (e.g., via connection 105 A), the REE capture unit 104 via connection 105B, the non-REE separation unit (not shown), one or more sensors (e.g., pressure sensors, pH sensors, among others), flow control devices, REE measurement units, among other system components. In one or more embodiments, the computer system, control system, or both may be in electronic communication with the pretreatment unit 102 (e.g., via connection 105 A), the REE capture unit 104 via connection 105B, the non-REE separation unit (not shown), one or more sensors (e.g., pressure sensors, pH sensors, among others), flow control devices, REE measurement units, among other system components.

[0060] FIG. 3 further depicts a simplified block diagram of a computer system (302).Computer (302) may be used to provide computational functionalities associated with methods, functions, processes, flows, and procedures as described in this disclosure, according to one or more embodiments. Computer (302) as shown in FIG. 3 is intended to encompass any computing device, such as a server, desktop computer, laptop / notebook computer, wireless data port, smart phone, personal data assistant (PDA), tablet computing device, one or more processors within these devices, or any other suitable processing device, including physical instances, virtual instances, or both of the computing device. Additionally, computer (302) can include an input device, such as a keypad, keyboard, touch screen, or other device that can accept user information. In some embodiments, computer (302) includes an output device that conveys information associated with the operation of the computer (302). The information associated with the operation of the computer may include digital data, visual, audio information, or combinations thereof, or a GUI.

[0061] Computer (302) can serve in a role as a client, network component, a server, a database or other persistency, any other component, or combinations thereof of a computer system for performing the subject matter described in the instant disclosure. Computer (302) may be communicably coupled with a network (330). In some implementations, one or more components of the computer (302) may be configured to operate withinPATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlenvironments, including cloud-computing-based, local, global, other environments, or a combination thereof.

[0062] At a high level, the computer (302) is an electronic computing device that, when in operation, is capable of receiving, transmitting, processing, storing, and / or managing data and information associated with the subject matter described herein. According to some implementations, computer (302) may also include or be communicab ly coupled with an application server, e-mail server, web server, caching server, streaming data server, business intelligence (BI) server, other server, or combinations thereof.

[0063] Computer (302) may receive requests over network (330) from a client application.For example, the computer may receive a request executed on another computer (302) via the network (330). In such embodiments, the computer may be capable of responding to the received requests by processing the said requests in an appropriate software application. A request may be sent to the computer (302) from internal users (e.g., from a command console and / or by other appropriate access method), external or third-parties, other automated applications, as well as any other appropriate entities, individuals, systems, or computers.

[0064] Each of the components of the computer (302) can communicate using a system bus (303). In some implementations, any or all of the components of the computer (302), hardware, software, or combinations thereof, may interface with each other, via interface (304), or a combination thereof, over the system bus (303) using an application programming interface (API) (312), a service layer (313), or any combination thereof. API (312) may include specifications for routines, data structures, and object classes. API (312) may be either computer-language independent or dependent and refer to a complete interface, a single function, or even a set of APIs. Service layer (313) provides software services to computer (302) or other components (whether or not illustrated in FIG. 3) that are communicably coupled to computer (302). The functionality of computer (302) may be accessible for all service consumers using this service layer. Software services, such as those provided by the service layer (313), provide reusable, defined business functionalities through a defined interface. For example, the interface may be software written in JAVA,PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlC++, or other suitable language providing data in extensible markup language (XML) format or another suitable format. While illustrated as an integrated component of computer (302), alternative implementations may illustrate API (312) or service layer (313) as stand-alone components in relation to other components of computer (302) or other components (whether or not illustrated in FIG. 3) that are communicably coupled to computer (302). Moreover, any or all parts of API (312) or service layer (313) may be implemented as child or sub-modules of another software module, enterprise application, or hardware module without departing from the scope of this disclosure.

[0065] As shown in FIG. 3, computer (302) includes an interface (304). In some embodiments, while illustrated as a single interface (304) in FIG. 3, two or more interfaces (304) may be used according to particular needs, desires, or particular implementations of the computer (302). Interface (304) is used by the computer (302) for communicating with other systems in a distributed environment that are connected to the network (330). Generally, interface (304) includes logic encoded in software, hardware, or a combination thereof. Interface (304) may be operable to communicate with the network (330). More specifically, interface (304) may include software supporting a communication protocol associated with communications such that network (330) or hardware of interface (304) is operable to communicate physical signals within and outside of computer (302).

[0066] Computer (302) includes at least one computer system (305), which can include a single processor or two or more processors according to particular needs, desires, or particular implementations of computer (302). Generally, computer system (305) executes instructions and manipulates data to perform the operations of computer (302) and any algorithms, methods, functions, processes, flows, and procedures as described in the instant disclosure.

[0067] As shown in FIG. 3, computer (302) includes a memory (306) that holds data for the computer (302), other components, or a combination thereof that can be connected to network (330). For example, memory (306) can be a database storing data consistent with this disclosure. While shown as a single memory (306) in FIG. 3, two or more memories may be used according to particular needs, desires, or particular implementations ofPATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlcomputer (302) and the functionality described herein. While memory (306) is illustrated as an integral component of computer (302), memory (306) can be external to the computer (302).

[0068] Application (307) of computer (302) is an algorithmic software engine providing functionality according to particular needs, desires, or particular implementations of the computer (302), particularly with respect to functionality described in this disclosure. For example, application (307) can serve as one or more components, modules, applications, among other functions. Further, although shown as a single application (307), multiple applications (307) may be used on computer (302). In addition, while shown as integral to the computer (302), application (307) can be external to the computer (302) in one or more embodiments.

[0069] In some embodiments, there may be any number of computers (302) associated with, or external to, a computer system containing computer (302), wherein each computer (302) communicates over network (330). Further, the term “client,” “user,” and other appropriate terminology may be used interchangeably as appropriate without departing from the scope of this disclosure. Moreover, many users may use one computer (302) or one user may use multiple computers (302).

[0070] METHOD FOR RECOVERING AN REE

[0071] In another aspect, embodiments herein relate to a method for recovering an REE.The method of recovering an REE in accordance with one or more embodiments may be capable of recovering one REE or a plurality of REEs (e.g., a mixture of two or more REEs, three or more REEs, four or more REEs, five or more REEs, six or more REEs, etc.). The REE may be an energy critical element as described previously, such as a lanthanide element, yttrium, scandium, germanium, gallium, or any combination thereof. The method may include providing an REE recovery system as described previously herein. The method may include recovering an REE enriched fluid from a dilute secondary source, such as a formation including mine-impacted water, acid mine drainage, a leachate (e.g., a coal ash leachate), or combinations thereof. The REE enriched fluid may be as previously described. In embodiments in which the REE enriched fluid includes a non-REE material,PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlsuch as an organic material (e.g., organic compounds) and / or a non-REE metal (e.g., cobalt, copper, magnesium , manganese, zinc, iron (Fe) and / or aluminum (Al)), the REE enriched fluid may be subject to separation to remove at least a portion of the non-REE material to produce an aqueous REE enriched fluid. A method 400 of one or more embodiments may be as shown in FIG. 4.

[0072] As shown in block 402, the method may include removing at least a portion of a non-REE component from the REE enriched fluid to produce a pretreated feed. The method of one or more embodiments may include pretreating an REE enriched feed. Pretreating the REE enriched feed may include adjusting a pH of the REE enriched feed. Adjusting the pH of the REE enriched fluid may include increasing the pH via the introduction of a pH adjusting agent to produce a pretreated fluid and a non-REE precipitate. The pretreated fluid may have a pH in a range as described previously. Increasing the pH of the REE enriched fluid may initiate the precipitation of at least a portion of a non-REE metal from the REE enriched fluid.

[0073] In some embodiments, the pH of the REE enriched feed is adjusted to a predetermined value. The predetermined value may be determined to maximize the removal of a non-REE component and to maintain the REE in the pretreated fluid. The pH adjusting agent and the REE enriched fluid may be agitated (e.g., mixed or stirred) for a predetermined period of time. The predetermined period of time for agitation may be determined based on the precipitation of the non-REE component while maintaining the pretreated fluid.

[0074] The non-REE precipitate may be removed from the pretreated fluid. In one or more embodiments, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 97%, at least 98%, at least 99%, or at least 99.5% of the non-REE components present in the REE enriched fluid are removed in the pretreatment step (e.g. , in pretreatment zone including pretreatment unit 102 of FIG. 1). The remaining 50%, 40%, 30%, 20%, 10%, 5%, 3%, 2%, 1%, or 0.5% of non-REE components present in the pretreated fluid may be present at a higher concentration as compared to a concentration of the REE present in the pretreated fluid. In some embodiments, at least a portion of the remaining non-REEPATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlcomponent present in the pretreated fluid may be present at a higher concentration as compared to a concentration of the REE present in the pretreated fluid. In some embodiments, the pretreated fluid can be passed directly to an REE adsorbing material (e.g., in an REE selective column) to capture at least one REE from the pretreated fluid.

[0075] In some embodiments, the pretreated fluid may be fed to a non-REE separation section or unit to reduce the concentration of the remaining non-REE components and produce a first extract as shown in block 404 of method 400. The pretreated feed passed to the non-REE separation section may be fed through at least one non-REE selective chromatography column such that non-REE components are retained on a stationary phase of the column and the REE permeates through the column in the first extract. In one or more embodiments, a wash solution is introduced to the at least one non-REE selective column to recover the non-REE selective components, regenerate the non-REE selective column(s) for a subsequent process, or any combination thereof.

[0076] In some embodiments, removing the non-REE selective component is repeated such that the first extract can be passed through the regenerated non-REE separation section until a predetermined non-REE selective component concentration is present below a predetermined value in the REE extract recovered from the non-REE separation section. In one or more embodiments, the pretreatment and feeding the pretreated fluid through the first section of the REE capture unit may remove at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 99%, at least 99.3%, at least 99.5%, at least 99.7%, or at least 99.9% of a non- REE component from the REE enriched fluid to produce a first extract.

[0077] In some embodiments, the first extract or a subsequent extract recovered from the non-REE separation section is passed to an REE separation unit of the REE capture unit. The REE may be recovered from the first extract, a subsequent extract, or both in the REE separation unit as shown in block 406 of the method 400 of FIG. 4. The REE separation unit may include an REE selective column. In one or more embodiments, the REE separation unit includes a minimum of two chromatography columns. The stationary phase of the minimum of two chromatography columns may each be selective for the same REEPATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlor different REEs. The stationary phase of the minimum of two chromatography columns may be the same or different. In some embodiments, the method includes functionalizing a solid support of a stationary phase with an REE selective molecule, such as an REE selective protein, an REE selective compound, or any combination thereof.

[0078] In one or more embodiments, at least a portion of the REE from the first extract is retained on the stationary phase of the REE selective column and an eluent (or second extract) is recovered from the column. A residual non-REE component may be removed from the column as the eluent. In some embodiments, the bed volume capacity of the stationary phase is reached such that REE breakthrough may be observed and an REE is present in the second extract. The REE selective column may be selected for an individual REE such that remaining REEs in solution are present in the second extract. The second extract may be passed to one or more additional columns in the REE capture unit to capture remaining REEs from the second extract. As mentioned previously, the one or more additional columns may be selective for the same REE or a different REE in solution as compared to the first REE selective column.

[0079] The REE retained on the REE selective column and, optionally, one or more additional columns are recovered by washing the columns with a wash solution. The wash solution breaks the bond between the stationary phase and the REE such that the REE is recovered in an eluent (or an REE “retentate” solution).

[0080] In one or more embodiments, the method includes measuring a non-REE content of an effluent, an REE content of an effluent, or any combination thereof. In some embodiments, the measuring includes obtaining a sample of the REE enriched fluid, the pretreated feed, an effluent recovered from a separation unit (e.g., an extract obtained from a column), a wash solution passed through a column, or any combination thereof. For example, a sample recovered from a column may be obtained after a predetermined number of bed volumes has been passed through the column. In some embodiments, the measuring includes performing Inductively Coupled Plasma - Optical Emission Spectrometry (ICP- OES) on the liquid sample.PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOl

[0081] A non-limiting example of a method in accordance with one or more embodiments may be as represented by the simplified process flow diagram of FIG. 5. In FIG. 5, fluids and their respective directions are labelled as with arrows 501A to 501L and 511. A fluid may be collected and / or transferred via manual operation. Alternatively, one of ordinary skill may appreciate that these arrows 501 A to 501L can include fluid transport lines such that one or more components of the process and system components are in fluid communication with a subsequent component. Such fluid transport lines may include one or more selected from pumps, valves, flow control equipment, sensors, among other components.

[0082] In FIG. 5, process 500 includes introducing an REE enriched feed to pretreatment unit 502 via fluid transport line 511. Pretreatment unit 502 may be as described previously (e.g., as described in pretreatment unit 102 in FIG. 1 and / or pretreatment unit 202 of FIG.2). As shown in FIG. 5, an REE enriched fluid containing a non-REE metal component may be introduced to a precipitation vessel 507 in precipitation zone 503. Precipitation zone 503 of pretreatment unit 502 may be configured to precipitate a non-REE component from the REE enriched feed such that a treated fluid is produced and transferred to the non- REE separation unit. A pH adjusting agent may be added to adjust the pH of the REE enriched fluid to produce a pretreated feed and precipitate a non-REE metal component. The non-REE precipitate may be collected via effluent line 501L.

[0083] The pretreated feed may then be fed to non-REE separation unit 505. Non-REE separation unit 505 may be as described previously (e.g., as in 205 of FIG. 2), which may be separate from and upstream of REE capture unit 504. In some embodiments, non-REE separation unit 505 can be located downstream of and separate from pretreatment unit 502. In some embodiments, and as shown in FIG. 5, non-REE separation unit 505 is located within pretreatment unit 502 and downstream of precipitation zone 503. In some embodiments, non-REE separation unit 505 is in fluid communication with an outlet of pretreatment unit 502 such that non-REE separation unit 505 is capable of receiving a pretreated fluid via flow line 501 A from vessel 501L.PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOl

[0084] Non-REE separation unit 505 is upstream of and in fluid communication with REE capture unit 504 such that. As shown in FIG. 5, unit 505 is a chromatography column. However, in one or more embodiments, non-REE separation unit 505 may include a chromatography column (e.g. , one chromatography column or at least two chromatography columns arranged in parallel and / or in series) such that the pretreated fluid is fed through the chromatography column to further remove a non-REE component from the pretreated feed.

[0085] The chromatography columns of one or more embodiments may be as described previously. For example, the chromatography column of the non-REE separation unit 505 may include an adsorbing material that is selective for non-REE components in a pretreated fluid. The non-REE component(s) present in a pretreated feed may include, but are not limited to, organic components, non-REE salts, transition metals (including, but not limited to, aluminum, iron, magnesium, calcium, among others).

[0086] An adsorbing material 516 of the chromatography column of non-REE separation unit 505 may be selective for non-REE components such that the adsorbing material is capable of selectively trapping the non-REE components from the pretreated fluid while the pretreated fluid is passed through unit 505. In one or more embodiments, the adsorbing material of the one or more chromatography columns of the non-REE separation unit 505 includes silica beads.

[0087] After passing the pretreated fluid through unit 505, a first extract containing the REE may be recovered via effluent line 501D and fed to REE capture unit 504. To regenerate the column of non-REE separation unit 505, receives a wash solution via flow line 501B from a first wash solution source 506. The first wash solution may include a component that removes non-REE components adsorbed on the chromatography column of the non-REE separation unit 505 to regenerate the chromatography column of the non- REE separation unit 505. The non-REEs captured in the non-REE separation unit 205 may be recovered in non-REE extract via flow line 501 C such that the REE is substantially absent from extract 501 C.PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOl

[0088] As mentioned previously, a first REE extract is recovered via flow line 501D from non-REE separation unit 505. The first REE extract may include an REE, a reduced concentration of a non-REE impurity component as compared to a pretreated fluid, and combinations thereof. The first REE extract may have a reduced concentration of non-REE components as compared to the pretreated feed. A pH of the first REE extract 20 ID may approximately be the same pH as the pretreated feed.

[0089] The first REE extract may be passed through REE capture unit 504 to selectively recover REEs (e.g., a lanthanide REE, germanium, yttrium, scandium, and / or gallium). As shown in FIG. 5, the REE effluent is split (e.g., between flow lines 501D and 501H) and separate streams are introduced into a first REE selective column 508 and a second REE selective column 510. While shown as being in parallel in FIG. 5, it may be envisioned that the columns of REE capture unit 504 may be arranged in parallel or a combination of in parallel and in series.. Each of the REE selective columns includes an absorbing material (represented by 514). The adsorbing material of column 508 and second column 510 may be the same or different. For example, the process 500 of FIG. 5 may include a different REE binding component in either or both of columns 508 and 510 for the purpose of recovering and purifying at least two or a plurality of different REEs. In some embodiments, an adsorbing material of a single REE selective column can include different REE binding components (i.e., proteins and / or small molecules) for the purpose of recovering and purifying multiple different REEs. The REE binding component of one or more embodiments may be selective for a lanthanide REE, germanium, yttrium, scandium, and / or gallium such that a lanthanide REE, germanium, yttrium, scandium, and / or gallium remains on the stationary phase as the first REE extract is passed through each of columns 508 and 510.

[0090] A second extract 501E may be recovered from column 508. Second extract 501E may have a reduced REE concentration as compared to the first extract 501D such that at least a portion of the REE from first extract 501D is adsorbed onto the adsorbing material of column 508. In one or more embodiments, an REE is substantially absent from second extract 501E. In one or more embodiments, an REE is present in extract 501E such that thePATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlextract is an REE permeate that may be fed to a subsequent REE separation unit (e.g., column 510) for further REE recovery.

[0091] The adsorbing material of the REE selective column may include, but is not limited to, REE selective proteins, REE selective compound, a solid phase support, or any combination thereof such that an REE is trapped (or bound) to the adsorbing material of the first REE separation column 508 while the first extract is passed through the column. The REE selective protein, REE selective compound, or both may be natural or synthetically engineered (e.g., with synthetic biology, synthetic chemistry, or both). The REE selective protein may include, but is not limited to, Lanmodulin (LanM) and / or variants of LanM. The variants of LanM may be produced via synthetic biology. As a nonlimiting example, the adsorbing material of the first REE selective column 508 may include LanM functionalized silica beads, silica beads functionalized with variants of LanM, or any combination thereof.

[0092] A second wash solution 501F may be applied to the first REE selective column 508 from a second wash solution source 512 to remove non-REE impurities from column 508, recover REEs bound to the adsorbing material of column 508, or any combination thereof. The second wash solution may include a dilute acidic solution (e.g., hydrochloric acid), an REE chelator, or any combination thereof. In some embodiments, REEs are desorbed from the adsorbing material 514 of column 508 via introduction of wash solution 501F. Non- REE impurities recovered from column 508, REEs bound to the adsorbing material of column 508, or any combination thereof may be recovered in a third extract 501 G after rinsing the column with the second wash solution 501F. In one or more embodiments, non- REE components are substantially absent from third extract 501 G such that the third extract 501 G is an REE retentate.

[0093] In some embodiments, at least a portion of the first extract (represented by 501H in FIG. 5), at least a portion of the second extract 501E and / or third extract 501 G, or combinations thereof are fed through second REE selective column 510 to produce a fourth extract 5011. In one or more embodiments, an REE is substantially absent from second extract 5011. In one or more embodiments, an REE is present in extract 5011 such that thePATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlextract is an REE permeate that may be fed to a subsequent REE separation unit (not shown in the process of FIG. 5) for further REE recovery.

[0094] The adsorbing material of the first REE selective column 508 and the adsorbing material of the second REE selective column 510 may be selective for the same REE, different REEs, or combinations thereof. The adsorbing material of the second REE selective column 510 may include REE selective proteins, REE selective small molecules, a solid-phase support, or any combination thereof such that an REE is bound to the adsorbing material. The REE selective protein, REE selective small molecule, a solidphase support, or any combination thereof may be as described previously. As a nonlimiting example, the second REE selective column may include silica beads functionalized with LanM and / or a LanM variant functionalized silica beads.

[0095] As shown in the process of FIG. 5, at least a portion of the second wash solution 501J may be introduced to column 510 to recover an REE, remove impurities, or any combination thereof to produce a fifth extract 501K. In one or more embodiments, nonREE components are substantially absent from the fifth extract 501K. The second wash solution may include a component to disrupt the binding of an REE from the REE selective molecule of the adsorbing material of column 510 such that the REE is included in the fifth extract 501K as an REE retentate effluent. In one or more embodiments, the REE is the major component of the third extract 501 G and / or the fifth extract 50 IK.

[0096] In some embodiments, a concentration of components in a solution and / or the eluents obtained from one or more columns are measured to determine if a step in the process requires repeating. For example, the concentration of components of a pretreated feed may be measured to determine if an additional pH adjustment requires repeating. In another example, the concentration of components in a first extract may be measured to determine if the first extract should be passed through a non-REE selective column.

[0097] In some embodiments, the method includes performing one or more steps (e.g., adjusting the pH of the REE enriched feed, introducing a feed to a non-REE selective unit and / or an REE selective unit, recovering the REE, measuring a component of a liquid sample, or any combination thereof) at a temperature in a range having a lower limit of anyPATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlone of 0, 2, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, and 80 °C and an upper limit of any one of 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, and 105 °C, where any lower limit can be paired with any mathematically compatible upper limit.

[0098] EXAMPLE

[0099] Purification of REEs from a mine-impacted water source (obtained from a Tier 1 mining company) was performed as shown in the simplified process flow diagram of FIG.5. Components and pH of the mine-impacted water prior to extraction is shown in Table 1 shown below, which indicates that the pH of the water is 2.9 and Al is the most abundant non-REE metal, which is followed by Fe, among other components. The concentrations of metal ions at pH 2.9 in the table represent the starting concentrations in the raw, untreated mine-impacted water feed.

[0100] Table 1 : Concentration of various metals in parts per million (ppm) at different pH.

[0101] Solutions of the untreated mine-impacted water feed were then separately adjusted to increase the pH of each solution. For example, in unit 502 of FIG. 5, the process for REE extraction included pretreatment, where a pH of the REE enriched water is first adjusted to precipitate most of the Al present in solution with the adjustment of the solution from a pHPATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlof 2.9 to about 5.0 as shown in Table 1. Each pH adjusted solution, as well as the untreated mine-impacted water, was measured for component concentration with ICP-OES. Out of the metals listed in Table 1, Al and Fe are the most challenging when extracting REEs as they interfere with the protein binding to REE in subsequent chromatographic separations. As shown in Table 1, adjustment of the solution pH to values between pH’s of 4.8 and 5 were able to mostly remove Fe and 95 to 99% Al.

[0102] As 1% Al was still high enough to interfere with REE binding to LanM protein, another Al-specific column was implemented to remove most of the remaining Al in water. The pretreatment was then followed by passing the pretreated feed through unit 505 including specialized beads (e.g., silica beads) that capture most of the remaining Al metal ions in a chromatography column. As shown in FIGs. 6A and 6B, minimal binding of REE, if any, was observed in Al specific column (FIG. 6A), and almost all the Al stayed in the column for the first 5 bed volumes (FIG. 6B). In particular, only Al was observed as being retained on the Al specific column. Breakthrough of Al after 6 bed volumes was observed, indicating the column had reached its capacity for binding Al.

[0103] Column 505 was regenerated (or “stripped”) via the introduction of an Al and Fe rinse solution, which was monitored with ICP-OES. Results of the components measured from the stripping are shown in FIGs. 7A and 7B. As shown in FIGs. 7A and 7B, only Al was observed in the eluent when the Al-specific column of unit 505 was stripped as negligible REEs were present in the strip solution, which further confirmed that this column was binding only to Al and not to REEs.

[0104] The REE extract was then recovered from the first column of unit 505 and was passed to unit 504 of FIG. 5, which involved selectively capturing REE from the REE extract using REE binding protein that was immobilized onto the surface-treated silica beads in two columns arranged in parallel. Each REE selective column (columns 508 and 510) received a portion of the first extract for separation.

[0105] For example, the first extract was split and passed through columns 508 and 510 that contained specially designed beads tethered with the REE-binding protein, LanM. This protein selectively binds REEs (FIG. 8A) while allowing residual non-REE metals, suchPATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlas copper, calcium, magnesium, iron and others, to pass through (as determined by the data presented in FIG. 8B). In particular, REEs were initially all retained in FIG. 8 A for the first 20 bed volumes before breakthrough, then some REEs were preferred over others with increasing bed volumes. As shown in FIG. 8B, Al was initially retained in the columns for the first 20 bed volumes and all other non-REE components passed directly through the columns.

[0106] Residual Al after pretreatment did bind to the column, illustrating the importance of the steps taken to remove most of the Al in the pretreatment zone and non-REE selective column of unit 505. This ion exchange-like process of FIG. 5 results in the retention of REEs in columns 508 and 510. The REEs were then readily desorbed and eluted with an REE wash solution at significantly higher concentrations (as shown in FIG. 9A), yielding a high-purity REE solution with minimal contamination from other cations except Al (Figure 9B). As shown in FIG. 9B, only Al was present at a significantly reduced concentration as compared to the untreated solution. In particular, this process significantly improved REE purity from an initial 0.003% to over 20% in the final product.

[0107] Embodiments herein advantageously unlock the potential of biological solutions and integrate them with innovative deployment methods and systems to support scalable technologies directed to the generation of domestic REE supply chains while reducing environmental impact. Advantageously, the systems and method described herein include a pretreatment and the removal of a non-REE component improves the extraction efficiency of the REE extraction. The system and methods herein may operate in an ion exchange-like process that results in the retention of only REEs in a column. The REEs may then be eluted at significantly and unexpectedly higher concentrations as compared to traditional systems and process, thereby yielding a high-purity REE solution with minimal contamination from other non-REE components, such as non-REE metal cations.

[0108] Throughout the application, ordinal numbers (for example, first, second, third) may be used as an adjective for an element (that is, any noun in the application). The use of ordinal numbers does not imply or create a particular ordering of the elements or limit any element to being only a single element unless expressly disclosed, such as by the usePATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlof the terms “before,” “after,” “single,” and other such terminology. Rather, the use of ordinal numbers is to distinguish between the elements. By way of an example, a first element is distinct from a second element, and the first element may encompass more than one element and succeed (or precede) the second element in an ordering of elements.

[0109] In the above description of FIGs. 1-9B, any component described with regard to a figure, in various embodiments disclosed herein, may be equivalent to one or more like- named components described with regard to any other figure. For brevity, descriptions of these components will not be repeated with regard to each figure. Thus, each and every embodiment of the components of each figure is incorporated by reference and assumed to be optionally present within every other figure having one or more like-named components. Additionally, in accordance with various embodiments disclosed herein, any description of the components of a figure is to be interpreted as an optional embodiment which may be implemented in addition to, in conjunction with, or in place of the embodiments described with regard to a corresponding like-named component in any other figure.

[0110] It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a rare earth element” (or “an REE”) includes reference to one or more REEs.

[0111] Terms such as “approximately” or “substantially” mean that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including, for example, tolerances, measurement error, measurement accuracy limitations, and other factors known to those of skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.

[0112] It is to be understood that one or more of the steps shown in the flowcharts may be omitted, repeated, or performed in a different order than shown. Accordingly, the scope disclosed should not be considered limited to the specific arrangement of steps shown in the flowcharts.

[0113] Although only a few example embodiments have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in thePATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlexample embodiments without materially departing from this invention. Accordingly, all such modifications are intended to be included within the scope of this disclosure as defined in the following claims.

Claims

PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOl CLAIMSWhat is claimed:

1. A method for recovering a rare earth element (REE) from an REE enriched feed, the method comprising:removing at least a portion of a non-REE component from the REE enriched feed to produce a pretreated feed;feeding the pretreated feed through a non-REE component separation unit to produce a first REE extract; andrecovering the REE from the first REE extract in an REE separation unit.

2. The method of claim 1, wherein the first REE extract comprises at least one REE and a reduced concentration of a non-REE component relative to the REE enriched feed.

3. The method of claims 1 or 2, wherein removing the non-REE component from the pretreated feed comprises:feeding the pretreated feed through a non-REE selective chromatography column.

4. The method of any one of the preceding claims, wherein recovering the REE from the first REE extract comprises:feeding the first REE extract through an REE selective column to produce a second REE extract, wherein:the REE selective column comprises an adsorbing material selective for the REE present in the first REE extract, andat least a portion of the REE is adsorbed onto the adsorbing material from the first REE extract.

5. The method of claim 4, wherein the REE selective column comprises an adsorbing material comprising an REE selective protein and a solid phase support.

6. The method of claims 4 or 5, further comprising:PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOlremoving the REE from the adsorbing material of the REE selective column by introducing a wash solution to the REE selective column; andrecovering the REE in the wash solution.

7. The method of any one of the preceding claims, further comprising:repeating the feeding of the first REE extract, the second REE extract, or combinations thereof through a non-REE selective column and / or the REE selective column.

8. The method of any one of the preceding claims, wherein the pretreating an REE enriched feed comprises:adjusting a pH of the REE enriched feed.

9. The method of claim 8, wherein adjusting the pH of the REE enriched feed comprises adjusting the pH to a value in a range from 3 to 5.5 to promote the formation of a precipitate comprising a non-REE component.

10. The method of claims 8 or 9, wherein adjusting the pH of the REE enriched feed comprises adjusting the pH to a value in a range from 4.5 to 5.0.

11. The method of any one of the preceding claims, wherein the pretreating and the capturing are performed at a temperature in a range from 0 °C to 105 °C.

12. The method of any one of the preceding claims, further comprising:controlling, by a computer system, a flow rate of one or more fluids selected from the REE feed, the pretreated feed, and the first extract that are introduced and / or removed from one or more selected from the pretreatment unit, the non-REE component separation unit, the REE separation unit, or any combination thereof.

13. The method of any one of the preceding claims, wherein the REE enriched feed is mine- impacted water, acid mine drainage, coal ash leachate, or any combination thereof.

14. The method of any one of the preceding claims, wherein a total concentration of REEs of the REE enriched feed is 500 ppm or less.PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOl15. The method of any one of the preceding claims, wherein the REE recovered is selected from the group consisting of a lanthanide element, germanium, yttrium, scandium, gallium, and combinations thereof.

16. The method of any one of the preceding claims, wherein the REE enriched feed comprises one REE or a mixture of REEs.

17. A system for recovering a rare earth element (REE) from an REE enriched feed, the system comprising:a pretreatment unit configured to pretreat the REE enriched feed and produce a pretreated feed; anda non-REE separation unit configured to produce a first REE extract; andan REE separation unit configured to recover the REE from the first REE extract.

18. The system of claim 17, wherein the pretreatment unit is configured to adjust a pH of the REE enriched feed.

19. The system of claims 17 or 18 wherein the REE separation unit comprises a minimum of two chromatography columns.

20. The system of any of claims 17 to 19, wherein the non-REE separation unit comprises at least one chromatography column comprising an adsorbing material selective for a non- REE component in the pretreated feed.

21. The system of any one of claims 17 to 20, wherein the REE separation unit is configured to retain an REE from the first extract.

22. The system of any of claims 19 to 21, wherein the non-REE separation unit, the REE separation unit or both further comprises at least one additional chromatography column.

23. The system of claim 22, wherein an adsorbing material of the at least one additional chromatography column of the REE separation unit is the same or different from an adsorbing material of the minimum of two chromatography columns of the REE separation unit.PATENT APPLICATION ATTORNEY DOCKET NO. 19148-OlOWOl24. The system of any one of claims 17 to 23, wherein the REE separation unit comprises at least one chromatography column comprising an REE selective protein, an REE selective small molecule, a solid phase support, or combinations thereof to selectively capture the REE from the pretreated feed.

25. The system of any one of claims 17 to 24, wherein the system further comprises a control system in electrical communication with the pretreatment unit, the REE separation unit, the non-REE separation unit, or any combination thereof.

26. The system of any one of claims 17 to 25, wherein the REE enriched feed is mine- impacted water, acid mine drainage, coal ash leachate, or any combination thereof.

27. The system of any one of claims 17 to 26, wherein a total concentration of REEs of the REE enriched feed is 500 ppm or less.

28. The system of any one of claims 17 to 27, wherein an REE present in the REE enriched feed is selected from the group consisting of a lanthanide element, germanium, yttrium, scandium, gallium, and combinations thereof.

29. The system of any one of claims 17 to 28, wherein the REE enriched feed comprises one REE or a mixture of REEs.

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