The Geothermal Technologies Office (GTO) funds prizes and competitions to encourage innovation and accelerate the development of new geothermal energy solutions. The GTO-funded American-Made Geothermal Lithium Extraction Prize seeks to drive forward the development of economic direct lithium extraction (DLE) from geothermal brines found in the Salton Sea/Imperial Valley area of Southern California

On Nov. 4, 2021, the U.S. Department of Energy (DOE) announced the Phase 1 semifinalists. Each team will receive $40,000 and will move on to Phase 2. In July 2022, DOE announced the five Phase 3 finalists that were awarded $280,000 and will move on to the final ”Fabricate & Test” phase. Learn more about these teams and their submissions below. If you have questions, please email DOE.Geothermal@ee.doe.gov.

Phase 3 Finalists

George Washington University – Team Ellexco 
Submission Title: Chemical-Free Extraction of Lithium from Brines 
Location: Washington, DC 
Phase 2 Award: $280,000
Project Summary: The submission proposes a electrochemical process workflow to extract lithium from geothermal brine that includes the following electrochemical processes: 1) electrochemical silica removal; 2) application of a lithium selective intercalation electrode plate layered with a monovalent-selective cation exchange membrane to separate lithium ions from solution; 3) release of the captured lithium and captured chloride into a recycled water solution; and 4) additional electrochemical filtration through anion exchange and bipolar membranes. The products produced include a lithium hydroxide solution, hydrochloric acid, and desalinated water for reuse in the electrochemical process. The lithium hydroxide solution will be concentrated through  vacuum evaporation.

Rice University – Team LiSED 
Submission Title: Lithium Selective ElectroDialysis 
Location: Houston, Texas 
Phase 2 Award: $280,000 
Project Summary: Two innovations to conventional cation exchange membranes (CEM) are presented to address lithium extraction. First, the development of a hybrid selective monovalent CEM to reject divalent cations by size exclusion separates calcium and magnesium ions from the brine. The proposed hybrid membrane consists of a CEM with a nanofiltration membrane attached, testing both a thin polyamide nanofiltration layer as well as a functionalized covalent organic framework layer. Second, a novel competing monovalent ion countering process using a reversed concentration gradient in the electrodialysis process reduces sodium and potassium ion transport across the membrane, resulting in a highly selective lithium extraction process. Lithium carbonate is produced with no pretreatment chemical addition, low water consumption, and high energy efficiency. 

University of Illinois Urbana-Champaign  Team SelectPureLi
Submission Title: A Redox Membrane for LiOH Extraction
Location: Urbana and Champaign, IL
Phase 2 Award: $280,000 
Project Summary: Select Pure Li proposed to use DirectPlateTM LiCoO2 (LCO) as a redox membrane to extract LiOH directly from geothermal brine. LCO is a classic lithium-ion battery cathode material that can be deposited on various material and form a dense film that is non-permeable to liquids. The team proposes that the use of a fully dense film might be more capable of blocking other non-lithium impurities present in brines (Na, K, Mg, Fe and silica, etc.) from passing through compared to other membranes. As a result, the LCO can work more effectively and can highly select lithium easier without additional impurities present. 

University of Utah – Team University of Utah 
Submission Title: Engineered Lithium Ion-Sieve Technology 
Location: Salt Lake City, Utah 
Phase 2 Award: $280,000 
Project Summary: To overcome many of the challenges associated current direct lithium extraction process from geothermal brines, University of Utah plans to develop a robust and economical approach utilizing Engineered Lithium-Ion Sieve Technology. The team hopes to demonstrate high separation factors by using a novel adsorption of lithium method that is endothermic (entropically driven) and thus increasing its selectivity with fluid temperature. These adsorbent materials can be synthesized from waste materials, which could reduce the sorbent material manufacturing cost and improving the overall techno-economics of the process. 

University of Virginia – Team TELEPORT 
Submission Title: "Targeted Extraction of Lithium with Electroactive Particles fOr Recovery Technology" 
Location: Charlottesville, Virginia 
Phase 2 Award: $280,000 
Project Summary: Team TELEPORT seeks to capture lithium using a selective solid intercalation material, electrodialysis, and downstream separation. The team hopes this combination of technology will be able to selectively extract lithium from geothermal brine. The technology will leverage existing solution chemistry to minimize the need for additional chemicals used in current technologies. By Phase 3, the team hopes to create a process for separation and purification that are scalable and space-efficient. 

Phase 2 Semifinalists

BOSTON UNIVERSITY – Pober-Strauss
Submission Title: DLE to LiOH with Ion Conducting Ceramic Membranes
Location: Boston, Massachusetts
Phase 1 Award: $40,000
Project Summary: The Pober-Strauss team proposes using lithium conducting ceramic membranes, separating hot brine from steam or superheated water. The team will use a voltage sent across a membrane system that will selectively transport lithium ions, eventually forming lithium hydroxide. The process will not need additional chemicals, could provide an energy cost savings, and has the potential for only needing a small membrane material to process a large amount of brine.

GEORGE WASHINGTON UNIVERSITY – Ellexco
Submission Title: Direct LiOH Production from Geothermal Brines
Location: Washington, DC
Phase 1 Award: $40,000
Project Summary: The submission proposes a electrochemical process workflow to extract lithium from geothermal brine that includes the following electrochemical processes: 1) electrochemical silica removal; 2) application of a lithium selective intercalation electrode plate layered with a monovalent-selective cation exchange membrane to separate lithium ions from solution; 3) release of the captured lithium and captured chloride into a recycled water solution; and 4) additional electrochemical filtration through anion exchange and bipolar membranes. The products produced include a lithium hydroxide solution, hydrochloric acid, and desalinated water for reuse in the electrochemical process. The lithium hydroxide solution will be concentrated through the application of vacuum evaporation

MASSACHUSETTS INSTITUTE OF TECHNOLOGY – Lithium from Home
Submission Title: Lithium from Home
Location: Cambridge, Massachusetts
Phase 1 Award: $40,000
Project Summary: Lithium from hybrid osmotic-electrokinetic membrane extraction utilizes a cascading membrane separation approach for selective recovery of monovalent ions from geothermal brine. First, the brine enters forward osmosis (FO) or pressure retarded osmosis (PRO) modules in a dilution stage. The diluted brine then enters a nanofiltration/monovalent selective electrodialysis stage to recover dissolved monovalent ions in a separate product stream using commercially available polyamide and polysulfide ion-exchange membranes. The monovalent ion stream is initially concentrated in the FO/PRO modules followed by an additional concentration stage using membrane distillation or osmotically assisted reverse osmosis. Finally, the concentrated monovalent ion stream enters a mixed suspension mixed product removal system to dissolve sodium and potassium carbonate and selectively recover lithium carbonate.

MASSACHUSETTS INSTITUTE OF TECHNOLOGY UNIVERSITY – Nanoporous Graphene Membrane
Submission Title: Filtering Lithium Ions with Graphene
Location: Cambridge, Massachusetts
Phase 1 Award: $40,000
Project Summary: The Nanoporous Graphene Membrane team proposes using a graphene nonporous atomically thin membrane that is a potentially transformative direct lithium extraction technology because it is capable of 1) significant selectivity between lithium and non-lithium ions; 2) high chemical stability; and 3) modest operating and capital costs. Using a novel graphene membrane, the pore size can be tuned precisely using a combination of pore creation and selectively sealing leaky pores. The team hopes to demonstrate, the feasibility of direct lithium extraction process from Salton Sea geothermal brines, that these membranes can also be manufactured quickly and cost effectively.

OREGON STATE UNIVERSITY – Espiku
Submission Title: Li2CO3 Using 2-Stage Thermal-Cyclonic Desalination
Location: Corvallis, Oregon
Phase 1 Award: $40,000
Project Summary: A three-step water treatment process is proposed to concentrate geothermal brine into a lithium solution. First, a thermal pump pressurizes the brine prior to pumping through a reverse osmosis (RO) unit. The mildly concentrated brine output from the RO unit is then fed into a pressure exchanger to repressurize the brine prior to pumping into a cyclonic desalination unit. Second, air jets atomize the brine into humid particle-laden air flow that is carried to the cyclonic desalination unit, where salt and humid air are separated, and water is condensed from the humid air, re-concentrating the brine output. The process relies on a meticulously controlled evaporation rate for oversaturation and precipitation of non-Li salts, resulting in a highly concentrated lithium brine solution. Third, sodium hydroxide is added to the brine to precipitate magnesium hydroxide; then sodium carbonate and heat are added to produce lithium carbonate.

RICE UNIVERSITY – LiSED
Submission Title: Highly Selective Electrodialysis for Li Extraction
Location: Houston, Texas
Phase 1 Award: $40,000
Project Summary: Two innovations to conventional cation exchange membranes (CEM) are presented to address lithium extraction. First, the development of a hybrid selective monovalent CEM to reject divalent cations by size exclusion separates calcium and magnesium ions from the brine. The proposed hybrid membrane consists of a CEM with a nanofiltration membrane attached, testing both a thin polyamide nanofiltration layer as well as a functionalized covalent organic framework layer. Second, a novel competing monovalent ion countering process using a reversed concentration gradient in the electrodialysis process reduces sodium and potassium ion transport across the membrane, resulting in a highly selective lithium extraction process. Lithium carbonate is produced with no pretreatment chemical addition, low water consumption, and high energy efficiency.

TEXAS TECH UNIVERSITY – Tech Desal
Submission Title: DLE with Intensified Membrane-Based Process
Location: Lubbock, TX
Phase 1 Award: $40,000
Project Summary: Tech Desal will design, establish, and demonstrate the performance of an intensified membrane distillation crystallization-nanofiltration (iMDC-NF) approach for direct lithium extraction. Geothermal brine will be send through the iMD unit, and pure water will be produced while an array of abundant minerals will precipitate in the crystallizer. The brine will be then directed to an nanofiltration extraction unit to separate highly valuable lithium.

UNIVERSITY OF ILLINOIS URBANA-CHAMPAIGN – SelectPureLi
Submission Title: Redox Membrane for LiOH Extraction
Location: Urbana and Champaign, IL
Phase 1 Award: $40,000
Project Summary: SlectPureLi propose to use DirectPlateTM LiCoO2 (LCO) as a redox membrane to extract LiOH directly from geothermal brine. LCO is a classic lithium-ion battery cathode material that can be deposited on various material and form a dense film that is non-permeable to liquids. The team proposes that the use of a fully dense film might be more capable of blocking other non-lithium impurities present in brines (Na, K, Mg, Fe and silica, etc.) from passing through compared to other membranes. As a result, the LCO can work more effectively and can highly select lithium easier without additional impurities present.

UNIVERSITY OF MASSACHUSETTS DARTMOUTH – Lirix-nano Sengupta
Submission Title: LiRIX-Nano
Location: North Dartmouth, MA
Phase 1 Award: $40,000
Project Summary: The LiRIX-Nano approach begins with divalent cation separation by passing geothermal brine through a perfluorophenylazide grafted copolymer nanofiltration membrane. The resulting solution is then pumped into a fixed bed column consisting of lithium selective cation exchange resin, and hydrochloric acid regenerant is added to the column. The acidified lithium chloride solution is then treated with ammonium carbonate, which is recycled within the process, resulting in the production of lithium carbonate with only hydrochloric acid and sodium hydroxide required as chemical inputs for the process.

UNIVERSITY OF MIAMI – Miami Solution
Submission Title: Innovative Electrochemical Lithium Extraction
Location: Coral Gables, Florida
Phase 1 Award: $40,000
Project Summary: Miami Solution aims to develop a process to economically and efficiently extract lithium from brines using an electrochemical method. The team aims to develop an innovative electrode that ensures high capture efficiency, high lithium yield, low pressure drop, and low fabrication cost. The proposed research and development project will prove the new concepts and aims to deliver a strategy offering a cost of <1 $/kg of lithium.

UNIVERSITY OF TEXAS AT AUSTIN – Freeman Lab
Submission Title: Direct Production of LiOH via Selective BPED
Location: Austin, Texas
Phase 1 Award: $40,000
Project Summary: A selective bipolar membrane electrodialysis approach to lithium extraction consists of alternating bipolar, selective cation-exchange, and selective anion-exchange membrane stacks configured within an electrochemical cell. Two product streams are generated—lithium hydroxide and hydrochloric acid—which can be used in the ion sorption process. The approach incorporates recent advancements in ion-selective nanomaterials for metal-organic frameworks in the proposed membrane materials.

UNIVERSITY OF UTAH – University of Utah
Submission Title: Engineered Lithium Ion-Sieve Technology
Location: Salt Lake City, Utah
Phase 1 Award: $40,000
Project Summary: To overcome many of the challenges associated current direct lithium extraction process from geothermal brines, University of Utah plans to developed a robust and economical approach utilizing Engineered Lithium-Ion Sieve Technology. The team hopes to prove their technology can demonstrate high separation factors by using a novel adsorption of lithium method that is endothermic (entropically driven) and thus increasing its selectivity with fluid temperature. These adsorbent materials can be synthesized from waste materials, which could reduce the sorbent material manufacturing cost and improving the overall techno-economics of the process.

UNIVERSITY OF VIRGINIA – Team TELEPORT
Submission Title: Team TELEPORT
Location: Charlottesville, Virginia
Phase 1 Award: $40,000
Project Summary: Team TELEPORT seeks to capture lithium using a selective solid intercalation material, electrodialysis, and downstream separation. The team hopes this combination of technology will be able to selectively extract lithium from geothermal brine. The technology will leverage existing solution chemistry to minimize the need for additional chemicals used in current technologies. By Phase 3, the team hopes to create a process for separation and purification that are scalable and space-efficient.

UNIVERSITY OF WYOMING – Bruce Parkinson’s Team
Submission Title: A Selective Membrane for LiOH in One Step
Location: Laramie, Wyoming
Phase 1 Award: $40,000
Project Summary: A chlor-alkali electrolysis cell utilizing a two-dimensional covalent organic framework membrane will be tested for lithium cation selectivity by controlling the pore size of the membrane. The ion size threshold of the membrane is proposed to exclude geothermal brine components such as potassium, sodium, magnesium, and calcium, while allowing only lithium ions to pass. Secondary byproducts of the electrolysis process include green hydrogen and chlorine gas. Additional concentration of the lithium hydroxide solution produced is proposed via waste heat from the geothermal power plant.

UNIVERSITY OF WYOMING – University of Wyoming Team Goldilocks
Submission Title: Goldilocks Ligands for Direct Lithium Recovery
Location: Laramie, Wyoming
Phase 1 Award: $40,000
Project Summary: The technology development focus of this project is to develop scalable nanofiltration membrane for lithium recovery from geothermal brines made from graphene. The technology proposed here would offer a low-cost, environmentally friendly, easy-to-scale method for rapid and efficient lithium extraction from a variety of brines using commercially available modules and cheap ligand compounds. At the end of Phase 1, the team plans to select the top three candidates of the ligand selection process, balancing optimal lithium yield and minimizing fouling and cost.