Graphene Could Turn Seawater Into Drinking Water
Researchers have tapped into graphene-oxide membranes as a new source to produce clean water.
A team from The University of Manchester have demonstrated the real-world potential of creating adequate clean water sources using graphene-oxide for new filtration technologies.
Graphene-oxide membranes have previously shown potential for gas separation and water filtration and graphene-oxide membranes developed at the National Graphene Institute at The University of Manchester have already demonstrated the potential of filtering out small nanoparticles, organic molecules and large salts.
However, prior to this study, graphene-oxide membranes could not be used for sieving common salts used in desalination technologies, which require very small sieves.
Previous research at The University of Manchester found that if immersed in water, graphene-oxide membranes become slightly swollen and smaller salts flow through the membrane along with water but larger ions or molecules were blocked.
The research team have now further developed the graphene membranes and found a strategy to avoid the swelling of the membrane when exposed to water.
The pore size in the membrane can be precisely controlled, allowing the sieving of common salts out of salty water, making it safe to drink.
When common salts are dissolved in water, they form a ‘shell’ of water molecules around the salt molecules, which allows the tiny capillaries of the graphene-oxide membranes to block the salt from flowing along with the water.
“This is the first clear-cut experiment in this regime.
However, the researchers believe that this technology has the potential to revolutionize water filtration across the world, particularly in countries that cannot afford large-scale desalination plants.