Research finds new lithium extraction method for reusing fracking wastewater
Reuse of wastewater produced from fracking could be a resource recovery boon with a new technology developed to extract lithium, which is used in the production of mobile phones, electric cars and other devices.
The technique employs a metal-organic framework made from a developed material that has a large internal surface, mimicking the filtering function of biological cell membranes during ‘ion selectivity’, to separate metal ions from water.
University of Texas at Austin Department of Chemical Engineering at the Cockrell School of Engineering Professor Benny Freeman told Mining Technology that the technique opens up a lot of opportunity for reusing waste materials from current mining practices in areas rich in lithium.
“Produced water from shale gas fields in Texas is rich in lithium,” he said.
“Advanced separation materials concepts such as ours could potentially turn this waste stream into a resource recovery opportunity.”
Each well can generate over 1ML of produced wastewater per week and Freeman estimated that enough lithium can be recovered to power 200 electric cars or 1.6 million smartphones from this amount of wastewater.
CSIRO Chief Scientist and Researcher Anita Hill said the new technique could help increase the amount of readily available lithium, in turn, bringing its market price down.
“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,” she said.
Successful implementation of the new extraction technique could also help to alleviate some of the concerns associated with fracking by promoting a circular economy.
Furthermore, the researchers said this method could also help with desalination, due to the ions being dehydrated as they pass through the membrane channels, which could prove to be cheaper and more cost effective than reverse osmosis.