Nov. 14 (UPI) -- Scientists have created a new graphene-oxide membrane capable of turning whiskey clear.
Previous graphene-oxide filters proved impermeable to all but water, limiting their potential. But researchers at the University of Manchester found they could let other solvents through by making the graphene-oxide membrane extremely thin.
During the membrane's assembly, pinholes become interwoven with graphene nanochannels, forming an atomic-scale sieve.
Researchers showed the new sieve could be used in organic solvent nanofiltration technology. OSN technology removes organic compounds from a solvent.
To showcase their new technology, scientists used the sieve to successfully remove organic dye particles as small as a nanometer from a methanol solvent.
They also turned whiskey clear.
"Just for a fun, we even filtered whisky and cognac through the graphene-oxide membrane. The membrane allowed the alcohol to pass through but removed the larger molecules, which gives the amber color," Rahul Nair, professor at Manchester's National Graphene Institute, said in a news release. "The clear whisky smells similar to the original whisky but we are not allowed to drink it in the lab, however it was a funny Friday night experiment!"
The membrane can be fine-tuned to filter out different-sized small particles while still allowing a fast flow-rate of larger molecules. The sieve's efficiency could help reduce the energy demands of filtration technologies.
"The developed membranes are not only useful for filtering alcohol, but the precise sieve size and high flux open new opportunity to separate molecules from different organic solvents for chemical and pharmaceutical industries," said researcher Yang Su. "This development is particularly important because most of the existing polymer-based membranes are unstable in organic solvents whereas the developed graphene-oxide membrane is highly stable."
Until now, graphene sieves have only been used for desalination and water filtration. The latest research, published this week in the journal Nature Materials, further expands the 2D material's already impressive repertoire.