Graphene sieve could make seawater drinkable

Graphene sieve could make seawater drinkable.
(CNN)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.
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.
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.
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.
Writing Monday in the Nature Nanotechnology journal, the team revealed it was able to restrict pore-swelling by coating the material with epoxy resin composite that prevented the sieve from expanding.
"This is the first clear-cut experiment in this regime.
We also demonstrate that there are realistic possibilities to scale up the described approach and mass produce graphene-based membranes with required sieve sizes," he added.
Boosting global access to water is critical.
Cities have been investing heavily in diversifying their water supplies, including developing new desalination technologies to make seawater potable.

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