Picture running seawater through a filter which can give you clean drinkable water–and creating enough power to run your smartphone or electric car.
That is what researchers from Monash University, in collaboration with CSIRO and the University of Texas at Austin, are hoping to do with a material called metal-organic frameworks, or MOFs.
MOFs are a sponge-like material that have the largest internal surface area of any known substance , which gives it the ability to capture, store and release chemicals at the atomic level. They are composed of designer synthetic crystals cooked up by chemists by stitching inorganic molecules together with organic molecules.
Their structures can also be tweaked to do different things, such as capturing carbon dioxide or delivering drug therapies. In this case, the MOF is fashioned into a device to remove the salt and lithium ions from seawater.
What this offers is a more energy-efficient, sustainable and cost-effective way to filter seawater (and other liquids) than current technologies, opening the door for breakthrough advances in the water and mining industries. The utility of MOFs in meeting global shortages of drinkable water is obvious: according to the World Health Organization, almost a third of the world’s population–some 2.1 billion people–lack access to safe drinking water. Millions die every year for reasons related to inadequate water supply, sanitation and hygiene.
Improvements that make it possible to produce more clean water, faster and more cheaply, would go a long way to help fill the supply gap and save lives.
More so, MOFs also show promise in meeting the power needs of Asia’s burgeoning populations, and the surging demand for green vehicles.
Southeast Asians are some of the most rampant consumers of electronics. On mobile phones alone, they spend an average 3.6 hours on mobile internet a day–the most in the world. The average American spends two hours, and the British 1.8 hours.
To battle sprawling pollution and modernize energy sources, Asian governments are also investing heavily to incentivize electric vehicle adoption. China alone bought up half of all electric cars sold in 2017, and the government wants one in five new cars sold–35 million–to be electric by 2025, while India is aiming to only sell electric cars in the country from 2030.
More on Forbes: China Could Be The World’s First All Electric Vehicle Ecosystem
Being far simpler and cheaper than digging through the ground, using MOFs to filter seawater and brine deposits offers a far more accessible way to unlock a crucial resource.
Seawater and brine are abundant with lithium ions, which make up the batteries that power electronic devices and electric vehicles. Lithium-ion batteries are popular because they can be recharged, but the extraction technology available today is struggling to dig it up as quickly as it is being used.
“While the world has plenty of lithium, it’s currently not being extracted and recycled quickly enough to match the demand for it,” Dr. Anita Hill, chief scientist at CSIRO and an author of the study, said by email.
Andrew Miller, senior analyst at Benchmark Mineral Intelligence, said, “With the huge growth projections for lithium ion battery demand into electric vehicles and stationary storage applications, the lithium market is at risk of being undersupplied for a number of years.”
“While brine is the lower-cost source of lithium, it takes longer to bring into the market and ramp up to significant volumes. If these systems can help extract additional lithium units, then they could play an important role in sustaining this growth.”
Having demonstrated its extraction capacities in a laboratory context, Dr. Hill and her colleagues are now looking into scaling up the device to a meaningful level.
“Additional studies are needed to optimize MOFs for commercial use and analyze long term stability,” said Hill. “Our future research will look into the concept further to see what can be produced and at what scale.”
More so, because they can be easily manipulated, MOFs are not restricted to extracting lithium and drinking water. With further development, Hill and her team believe that MOFs could also be used in processing more complex liquids, like agricultural runoff or the waste streams from mining operations.
However, Dave Buckley, vice president of Piedmont Lithium, an Australian mineral resource company with a focus on lithium extraction, expects it will be a while yet before we can see these filters in our shops and seas.
While Buckley agreed that MOFs are a “potential game changer,” he also argued that it will require considerably more work–such as separating more complex ions–and suggested that it could be 10 years before MOFs could be used in an industrial context.
It’s hard to pinpoint when a developing technology will come to market; what is certain is it will take time to create a device that lets us decide which chemicals to keep and which to filter on an atomic scale.
With developments like this, however, the reality of a filter that both hydrates you and powers the machines on which we have come to depend is coming closer.
Related: Emerging Asia Hits a Wall of Water