A collaboration between the teams of Dr Huacheng Zhang, Professor Huanting Wang and Associate Professor Zhe Liu at Monash University in Melbourne, in conjunction with Dr Anita Hill of CSIRO and Professor Benny Freeman of the McKetta Department of Chemical Engineering at The University of Texas at Austin, has recently revealed that MOF membranes can mimic the filtering function, or 'ion selectivity', of organic cell membranes.
With further development, these membranes display significant potential to remove salts from seawater and separate metal ions in a highly efficient and cost-effective manner. The discovery, published on February 9 in Science Advances, represents a revolutionary new technological approach for the water and mining industries, with improved energy consumption versus today’s most advanced water purification technologies.
Monash University’s Professor Huanting Wang said in a statement, “We can use our findings to address the challenges of water desalination. Instead of relying on the current costly and energy intensive processes, this research opens up the potential for removing salt ions from water in a far more energy efficient and environmentally sustainable way.”
“This is just the start of the potential for this phenomenon. We’ll continue researching how the lithium ion selectivity of these membranes can be further applied. Lithium ions are abundant in seawater, so this has implications for the mining industry who current use inefficient chemical treatments to extract lithium from rocks and brines. Global demand for lithium required for electronics and batteries is very high. These membranes offer the potential for a very effective way to extract lithium ions from seawater, a plentiful and easily accessible resource.”
Building on the growing scientific understanding of MOFs, CSIRO’s Dr Anita Hill said the research offers another potential real-world use for the next-generation material. “The prospect of using MOFs 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 for Australia,” Dr Hill said.
The University of Texas in Austin Professor Benny Freeman says, “Produced water from shale gas fields in Texas is rich in lithium. Advanced separation materials concepts, such as this, could potentially turn this waste stream into a resource recovery opportunity. I am very grateful to have had the opportunity to work with these distinguished colleagues from Monash and CSIRO via the Australian-American Fulbright Commission for the U.S. Fulbright Distinguished Chair in Science, Technology and Innovation sponsored by the Commonwealth Scientific and Industrial Research Organization (CSIRO).”