A research team of theUniversity of Manchesterin the United Kingdom, developed one Graphene oxide based membrane Able to filter the salt with sea water with precision. A discovery that could really change the fate of millions of people all over the world that, still today,.
Published in the magazine Nature Nanotechnologythe study led by Dr. Rahul Nair shows how, thanks to the use of an epoxy resin to limit the expansion of the membrane, it was possible to obtain a efficient, scalable and cheap barrier. A result that opens concrete scenarios for use on a large scale of this material, already known for its extraordinary mechanical and conductive properties.
How it works
The graphenediscovered in 2004 always at the University of Manchester, it is made up of a single layer of carbon atoms arranged in a hexagonal grid. Despite its exceptional qualities, including the traction resistance and high electrical conductivityproduce it in large quantities and low has proved to be very complicated.
On the contrary, its chemical derivative, thegraphene oxideis much easier to obtain. As Dr. Nair explained to the BBC, it can be transformed into a solution or ink e applied on porous materialsbecoming a useful membrane for filtering. And here comes the real news: thanks to a system that block the swelling of the membrane when it is immersed in water – one of the limits that in the past prevented the filtration of the smallest salts – the sieve is now capable of also retain sodium chloride.
When the salt melts in the water, in fact, each molecule surrounds a small “shell” formed by water molecules. THE Membrane channels in oxide graphenehaving dimensions lower than a nanometerthey are too tight to allow the passage of this complex. Pure water, however, manages to pass freely.
The result? Only the water is filteredleaving the salts behind it. And thanks to the structure of the channels, the molecules move quickly and orderly, as on one molecular assembly linefacilitating the filtration process with reduced energy consumption.
Why can it really change the future of water?
There global water crisis It is one of the most serious and underestimated problems of our time. The United Nations they estimate that by 2025 well the 14% of the world population It will face the scarcity of water. And climate change, with its devastating effects on water basins and slopes, will only make the situation worse.
In this context, Technologies such as graphene oxide they could make a difference. Currently, most of the desalinization systems use polymer membraneswhich require frequent maintenance and high energy use. Furthermore, they do not always manage to effectively filter all the salts and tend to deteriorate over time, also because of the so -called biofoulingthat is, the accumulation of organic substances that obstruct the pores.
Second RAM Devanathanof the Pacific Northwest National Laboratory in the United States, to bring this technology to an industrial level it will be necessary to work on the Resistance and durability of the membraneas well as on its production cost. But the potential is enormous.
The selective separation of water from ions through the physical restriction of the space between the layers opens the way to the creation of economic and efficient membranes.
The goal is clear: to develop A filtration system capable of transforming sea water and water reflua into drinking waterwith a minimum energy and environmental impact.
And in a world where thewater is becoming an increasingly scarce asseteven in the so -called “developed” countries, such an innovation can no longer remain only in the workshops.
