CSIRO scientists supercharge water purification

CSIRO scientists have supercharged water purification, making it simpler, more effective and quicker, using their own specially designed form of graphene, 'Graphair'.

The new filtering technique is so effective, water samples from Sydney Harbour were safe to drink after passing through the filter.

"Almost a third of the world's population, some 2.1 billion people, don't have clean and safe drinking water," the paper's lead author, CSIRO scientist Dr Dong Han Seo, said. "As a result, millions — mostly children — die from diseases associated with inadequate water supply, sanitation and hygiene every year.

"In Graphair we've found a perfect filter for water purification. It can replace the complex, time-consuming and multi-stage processes currently needed with a single step."

A Graphair sample. Image credit: ©CSIRO

While graphene is the world's strongest material and can be just a single carbon atom thin, it is usually water repellent. Using their Graphair process, CSIRO researchers were able to create a film with microscopic nano-channels that let water pass through, but stop pollutants.

As an added advantage Graphair is simpler, cheaper, faster and more environmentally friendly than graphene to make. It consists of renewable soybean oil, more commonly found in vegetable oil.

Looking for a challenge, Dr Seo and his colleagues took water samples from Sydney Harbour and ran it through a commercially available water filter, coated with Graphair. Researchers from QUT, the University of Sydney, UTS and Victoria University then tested and analysed its water purification qualities.

"This technology can create clean drinking water, regardless of how dirty it is, in a single step," Dr Seo said. "All that's needed is heat, our graphene, a membrane filter and a small water pump."

The breakthrough research has been published in Nature Communications.

Top image: Dr Seo takes a sample of water from Sydney Harbour. Image credit: ©CSIRO