US-12623913-B2 - Process for selective adsorption and recovery of lithium from natural and synthetic brines

Abstract

This invention relates generally to a process for selective adsorption and recovery of lithium from natural and synthetic brines, and more particular to a process for recovering lithium from a natural or synthetic brine solution by passing the brine solution through a lithium selective adsorbent in a continuous countercurrent adsorption and desorption circuit.

Inventors

• Charles R. Marston
• Michael J. Garska

Assignees

• ENERGYSOURCE MINERALS LLC

Dates

Publication Date

20260512

Application Date

20220620

Claims (20)

1. 1 . A continuous countercurrent adsorption and desorption process for recovery of an enhanced lithium product solution from a lithium-containing brine solution, said process comprising the cyclical and sequential steps of: pumping fluid flow through a continuous countercurrent adsorption and desorption circuit comprising an adsorption displacement zone, an adsorption loading zone, an entrainment rejection zone, and an elution zone, each of said zones comprising one or more adsorbent beds or columns having a lithium selective adsorbent; said process further comprising: a) recycling a portion of a lithium product eluate from the elution zone to the adsorption displacement zone and displacing residual feed brine from the one or more adsorbent beds or columns in the adsorption displacement zone to form a displacement feed brine; b) pumping the displacement feed brine from the adsorption displacement zone and the lithium-containing brine solution through the adsorption loading zone to adsorb lithium in the displacement feed brine and the lithium-containing brine solution on the lithium selective adsorbent in the one or more adsorbent beds or columns and form a lithium-depleted brine raffinate; c) pumping the lithium-depleted brine raffinate from the adsorption loading zone through the entrainment rejection zone and displacing a latent eluate solution from the one or more adsorbent beds or columns in said entrainment rejection zone using a portion of said lithium-depleted brine raffinate; d) pumping said displaced latent eluate solution and a portion of an eluant solution through said elution zone to desorb a portion of the lithium on the lithium selective adsorbent in the one or more adsorbent beds or columns and form said lithium product eluate; and e) collecting a portion of said lithium product eluate as an enhanced lithium product solution.
2. 2 . The process of claim 1 wherein said elnant solution comprises lithium chloride and water at a concentration of up to about 1000 mg/kg lithium.
3. 3 . The process of claim 1 further comprising recovering lithium from said enhanced lithium product solution.
4. 4 . The process of claim 3 further comprising selectively converting said recovered lithium to lithium carbonate, lithium hydroxide, or both.
5. 5 . The process of claim 3 further comprising dewatering said enhanced lithium product solution using membrane separation.
6. 6 . The process of claim 5 wherein said membrane separation comprises reverse osmosis or nanofiltration.
7. 7 . The process of claim 6 wherein said dewatered enhanced lithium product solution has a concentration from about 3000 to about 5000 mg/kg lithium.
8. 8 . The process of claim 5 further comprising concentrating said dewatered enhanced lithium product solution to produce a high lithium concentration, enhanced lithium product solution and a recycle eluant solution.
9. 9 . The process of claim 8 further comprising providing said enhanced lithium product solution, said high lithium concentration, enhanced lithium product solution, or both to a lithium solvent extraction and electrowinning process, a solvent extraction and membrane electrolysis process, or a recovery process for production of high purity lithium hydroxide and lithium carbonate for battery production.
10. 10 . The process of claim 8 wherein said dewatered and concentrated enhanced lithium product solution has a concentration from about 5000 to about 30000 mg/kg lithium.
11. 11 . The process of claim 3 wherein said enhanced lithium product solution has a concentration of greater than 3000 mg/kg lithium.
12. 12 . The process of claim 1 wherein said lithium-containing brine solution comprises a natural brine, a synthetic brine, a polished brine, or a combination thereof.
13. 13 . The process of claim 1 wherein said lithium-containing brine solution comprises a continental brine, a geothermal brine, an oil field brine, a brine from hard rock lithium mining, or a combination thereof.
14. 14 . The process of claim 1 wherein said lithium selective adsorbent is a lithium alumina intercalate prepared from hydrated alumina, a lithium aluminum layered double hydroxide chloride, a layered double hydroxide modified activated alumina, a layered double hydroxide imbibed ion exchange resin or copolymer or molecular sieve or zeolite, layered aluminate polymer blends, a lithium manganese oxide, a titanium oxide, an immobilized crown ether, or a combination thereof.
15. 15 . The process of claim 1 wherein said continuous countercurrent adsorption and desorption circuit comprises a multi-port valve system.
16. 16 . The process of claim 15 , wherein the multi-port valve system is a rotary multi-port valve system.
17. 17 . The process of claim 16 wherein said fluid flow through said adsorption displacement zone, said adsorption loading zone, said entrainment rejection zone, and said elution zone of said continuous countercurrent adsorption and desorption circuit is controlled by pumping flow rates, predetermined indexing, or a combination of both of said rotary multi-port valve system.
18. 18 . The process of claim 17 wherein: said adsorption displacement zone is positioned upstream with respect to fluid flow of said adsorption loading zone; said adsorption loading zone is positioned upstream with respect to fluid flow of and in fluid communication with said entrainment rejection zone; said entrainment rejection zone positioned upstream with respect to fluid flow of and in fluid communication with said elution zone; and said elution zone in fluid communication with said adsorption displacement zone.
19. 19 . The process of claim 18 further comprising passing said lithium-containing brine solution through said adsorption loading zone for a predetermined amount of contact time.
20. 20 . The process of claim 17 further comprising pumping said fluid flow through said adsorption displacement zone, said adsorption loading zone, said entrainment rejection zone, and said elution zone of said continuous countercurrent adsorption and desorption circuit in a direction countercurrent to the predetermined indexing of said adsorbent beds or columns through said adsorption displacement zone, said adsorption loading zone, said entrainment rejection zone, and said elution zone of said continuous countercurrent adsorption and desorption circuit.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application claims priority to and is a divisional application of U.S. patent application Ser. No. 16/402,931, filed May 3, 2019, now U.S. Pat. No. 1,365,128, issued Jun. 21, 2022, which claims the benefit of U.S. Provisional Patent Application No. 62/671,489 filed on May 15, 2018 and also is a continuation-in-part of U.S. patent application Ser. No. 16/010,286 filed on Jun. 15, 2018, which claims the benefit of U.S. Provisional Patent Application No. 62/520,024 filed on Jun. 15, 2017 and the benefit of U.S. Provisional Patent Application No. 62/671,489 filed on May 15, 2018. This application incorporates each of the foregoing applications by reference into this document as if fully set out at this point. BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to a process for selective adsorption and recovery of lithium from natural and synthetic brines, and more particular to a process for recovering lithium from a natural or synthetic brine solution by contacting the brine solution with a lithium selective adsorbent using a continuous countercurrent adsorption and desorption (“CCAD”) process. 2. Description of the Related Art Seawater contains about 0.17 mg/kg, and subsurface brines may contain up to 4,000 mg/kg, more than four orders of magnitude greater than sea water. Typical commercial lithium concentrations are between 200 and 1,400 mg/kg. In 2015, subsurface brines yielded about half of the world's lithium production. The Salton Sea Known Geothermal Resource Area (“SSKGRA”) has the most geothermal capacity potential in the United States. Geothermal energy, the harnessing of heat radiating from the beneath the Earth's crust, is a renewable resource that is capable of cost-effectively generating large amounts of power. In addition, the SSKGRA has the potential to become North America's prime sources of alkali metals, alkaline earth metals and transition metals, such as lithium, potassium, rubidium, iron, zinc and manganese. Brines from the Salton Sea Known Geothermal Resource Area are unusually hot (up to at least 390° C. at 2 km depth), hypersaline (up to 26 wt. %), and metalliferous (iron (Fe), zinc (Zn), lead (Pb), copper (Cu)). The brines are primarily sodium (Na), potassium (K), calcium (Ca) chlorides with up to 25 percent of total dissolved solids. While the chemistry and high temperature of the Salton Sea brines have led to the principal challenges to the development of the SSKGA, lithium and other brine elements typically maintain high commodity value and are used in a range of industrial and technological applications. The “lithium triangle” of Chile, Argentina and Bolivia is where approximately 75% of the world's lithium comes from. Chile is currently the second largest producer of lithium carbonate and lithium hydroxide, which are key raw materials for producing lithium-ion batteries, behind only Australia. Salar de Atacama is one of the hottest, driest, windiest and most inhospitable places on Earth, and the largest operations are in the shallow brine beneath the Salar de Atacama dry lakebed in Chile, which as of 2015, yielded about a third of the world's supply. The Atacama in Chile is ideal for lithium mining because the lithium-containing brine ponds evaporate quickly, and the solution is concentrated into high-grade lithium products like lithium carbonate and lithium hydroxide. Mining lithium in the salars of Chile and Argentina is much more cost-effective than hard rock mining where the lithium is blasted from granite pegamite orebodies containing spodumene, apatite, lepidolite, tourmaline and amblygonite. The shallow brine beneath the Salar de Uyuni in Bolivia is thought to contain the world's largest lithium deposit, often estimated to be half or more of the world's resource; however, as of 2015, no commercial extraction has taken place, other than a pilot plant. The mining of lithium from brine resources in the “lithium triangle” historically depends upon easy access to large amounts of fresh water and very high evaporation rates. With declining availability of fresh water and climate change, the economic advantage of conventional processing techniques is disappearing. Fixed-bed and continuous countercurrent ion exchange (“CCIX”) systems have been used to recover metals, such as nickel (Ni) and cobalt (Co), from ore leach solutions. While fixed-bed systems are generally used in recovery projects, they are known to require relatively large amounts of water and chemicals and the performance is generally weaker than CCIX systems. Utilizing CCIX-type equipment in the adsorption of lithium from brines with lithium selective adsorbents in a CCAD circuit will bring increased process efficiency versus classical fixed-bed processing. The water and reagent efficiency of a CCAD circuit/process should be a preferred replacement for evaporation ponds in the brine mining operations in the salars of “lithium triangle”, s