Researchers in the United Kingdom have developed a graphene-based sieve that can filter salt out of seawater, a development that could provide drinking water to millions of people around the globe.
The applications could be a game-changer in countries where access to safe, clean, drinkable water is severely limited.
About
Graphene -- an ultra-thin sheet of carbon atoms organized in a hexagonal lattice -- was first identified at the University of Manchester in 2002 and has since been hailed as a "wonder material," with scientists racing to develop inexpensive graphene-based barriers for desalination on an industrial scale. Overcoming hurdles
In recent years, there had been some success in water filtration using graphene oxide to sift out other smaller nanoparticles and organic molecules.
But researchers had struggled to move forward after finding that the membrane's pores would swell up when immersed in water, allowing particles to continue to pass through.
Now, the team at Manchester has used a compound of graphene, known as graphene oxide, to create a rigid sieve that could filter out salt using less energy.
Global implications
Boosting global access to water is critical.
By 2025, 14% of the global population will suffer from water scarcity, the United Nations predicts.
In addition, climate change is expected to wreak havoc on urban water supplies, with decreased rainfall and rising temperatures expected to fuel demand.
Cities have been investing heavily in diversifying their water supplies, including developing new desalination technologies to make seawater potable. But existing, industrial-scale desalination plants can be costly and normally involve one of two methods: distillation through thermal energy, or filtration of salt from water using polymer-based membranes.
These techniques have drawn criticism from environmentalists, who argue they involve large amounts of energy, produce greenhouse gases and can be harm marine organisms.
