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New tech cheaply produces lithium and H2, while desalinating seawater

14 points by mardiyah 5y ago

cjbenedikt 5y ago
"implies that after lithium harvest, the remaining water can be treated as freshwater. Hence, the process also has a potential to integrate with seawater desalination to further enhance its economic viability." That doesn't meant it IS desalinated yet. It "implies" and has "potential"...isn't the same.
peter_d_sherman 5y ago
>"According to researchers at Saudi Arabia's King Abdullah University of Science and Technology (KAUST), there's about 5,000 times as much lithium in the oceans as there is in land deposits, and a newly developed technology could start extracting it cheaply enough to make the big time – while producing hydrogen gas, chlorine gas and desalinated water as a bonus. The process relies on an electrochemical cell containing a ceramic membrane made from lithium lanthanum titanium oxide (LLTO), with pores just wide enough to let lithium ions through while blocking larger metal ions. “LLTO membranes have never been used to extract and concentrate lithium ions before,” says post-doctorate researcher Zhen Li, who developed the cell. The cell has three compartments. Seawater flows into the first, from which positively charged lithium ions pass through the LLTO membrane into a second compartment holding a buffer solution and a copper cathode coated with platinum and ruthenium. Negatively charged ions, meanwhile, go through an anion exchange membrane into a third compartment containing a sodium chloride solution, where they're attracted to a platinum-ruthenium anode. The lithium is pulled through the LLTO membrane toward the cathode when a current is applied, and the process generates hydrogen gas at the cathode and chlorine gas at the anode, both of which can be collected. Where lithium starts out at a concentration of just 0.2 parts per million in unprocessed seawater, experiments found that running it through this cell in five 20-hour stages enriched the concentration to over 9,000 parts per million, leaving a solution that was pH-adjusted, centrifuged, rinsed and dried to leave a lithium phosphate powder of 99.94 percent purity, meeting standards for battery-grade lithium phosphate."
WalterGR 5y ago
Also see: https://news.ycombinator.com/item?id=27411631 https://news.ycombinator.com/item?id=27411631 Scientists develop ‘cheap and easy’ method to extract lithium from seawater (https://www.mining.com/scientists-develop-cheap-and-easy-method-to-extract-lithium-from-seawater/ https://www.mining.com/scientists-develop-cheap-and-easy-met...) 493 points | sambeau | 4 days ago | 282 comments

14 points by mardiyah 5y ago

"implies that after lithium harvest, the remaining water can be treated as freshwater. Hence, the process also has a potential to integrate with seawater desalination to further enhance its economic viability." That doesn't meant it IS desalinated yet. It "implies" and has "potential"...isn't the same.

peter_d_sherman 5y ago

>"According to researchers at Saudi Arabia's King Abdullah University of Science and Technology (KAUST), there's about 5,000 times as much lithium in the oceans as there is in land deposits, and a newly developed technology could start extracting it cheaply enough to make the big time – while producing hydrogen gas, chlorine gas and desalinated water as a bonus. The process relies on an electrochemical cell containing a ceramic membrane made from lithium lanthanum titanium oxide (LLTO), with pores just wide enough to let lithium ions through while blocking larger metal ions. “LLTO membranes have never been used to extract and concentrate lithium ions before,” says post-doctorate researcher Zhen Li, who developed the cell. The cell has three compartments. Seawater flows into the first, from which positively charged lithium ions pass through the LLTO membrane into a second compartment holding a buffer solution and a copper cathode coated with platinum and ruthenium. Negatively charged ions, meanwhile, go through an anion exchange membrane into a third compartment containing a sodium chloride solution, where they're attracted to a platinum-ruthenium anode. The lithium is pulled through the LLTO membrane toward the cathode when a current is applied, and the process generates hydrogen gas at the cathode and chlorine gas at the anode, both of which can be collected. Where lithium starts out at a concentration of just 0.2 parts per million in unprocessed seawater, experiments found that running it through this cell in five 20-hour stages enriched the concentration to over 9,000 parts per million, leaving a solution that was pH-adjusted, centrifuged, rinsed and dried to leave a lithium phosphate powder of 99.94 percent purity, meeting standards for battery-grade lithium phosphate."

WalterGR 5y ago

Also see: https://news.ycombinator.com/item?id=27411631 https://news.ycombinator.com/item?id=27411631 Scientists develop ‘cheap and easy’ method to extract lithium from seawater (https://www.mining.com/scientists-develop-cheap-and-easy-method-to-extract-lithium-from-seawater/ https://www.mining.com/scientists-develop-cheap-and-easy-met...) 493 points | sambeau | 4 days ago | 282 comments