New membrane extracts lithium from fracking waste water

As EVs proliferate, global demand for lithium is rapidly outpacing the rate at which it can be mined or recycled, but an international team of researchers are working on a solution.

Professor Benny Freeman of the University of Texas, and his colleagues at Monash University and the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia have discovered a new way to extract lithium from water.

In a paper published in Science Advances, the team describes a metal-organic-framework membrane that mimics the filtering function, or “ion selectivity,” of biological cell membranes. The membrane process efficiently separates metal ions, offering a possible way to extract lithium from waste water from the mining industry.

The waste water generated by hydraulic fracturing in some areas of Texas has high concentrations of lithium, which could be extracted by the team’s membrane filter. “Produced water from shale gas fields in Texas is rich in lithium. Advanced separation materials concepts such as ours could potentially turn this waste stream into a resource recovery opportunity,” Freeman said.

Each well in Texas’s Barnett and Eagle Ford formations can generate up to 300,000 gallons of water per week. Using their new process, Freeman and his team estimate that just one week’s worth of waste water could yield enough lithium for 200 EV battery packs.

“The prospect of using metal-organic frameworks for sustainable water filtration is incredibly exciting from a public-good perspective, while delivering a better way of extracting lithium ions to meet global demand could create new industries,” said Anita Hill, CSIRO’s Chief Scientist.

 

Source: EurekAlert!