APR 06, 2017 7:34 AM PDT

Turning salt into water: new technology leads the way for desalination

As access to fresh water becomes scarcer, the search to find a resource efficient method of desalination becomes ever more urgent. According to the United Nations, 85% of the world population lives in the driest half of the planet and 783 million people do not have access to clean water. Every year, 6 to 8 million people die from the consequences of disasters and water-related diseases. As we continue to pump carbon dioxide into our atmosphere from our excessive use of fossil fuels, our planet continues getting drier and hotter, melting and evaporating crucial sources of freshwater that people, animals, and plants depend on.

Landscapes are becoming drier. Photo: The Huffington Post

Luckily, scientists from the University of Manchester, led by Dr. Rahul Nair, have developed a graphene oxide sieve that could potentially be highly efficient at filtering salts. Their results, published recently in the journal Nature Nanotechnology, introduce the membrane that will separate salts from water, producing potable water from salt water.  

Graphene itself consists of a single layer of carbon atoms arranged in a hexagonal lattice. It has an extraordinary tensile strength and electrical conductivity, but as of now producing large quantities of single-layer graphene via a method called chemical vapour deposition (CVD) is painstaking and expensive. This is why the team began investigating graphene oxide, the cousin of graphene.

Dr. Nair stated that "Graphene oxide can be produced by simple oxidation in the lab.” He told BBC News, "As an ink or solution, we can compose it on a substrate or porous material. Then we can use it as a membrane. In terms of scalability and the cost of the material, graphene oxide has a potential advantage over single-layered graphene."

This graphene oxide option is more plausible than using a single-layer graphene because the single-layer is difficult to make permeable without letting the salt slip through. “You have to make a membrane with a very uniform less-than-one-nanometre hole size to make it useful for desalination. It is a really challenging job," Nair said.

The technology may have other uses as well. “The membranes are not only useful for desalination, but the atomic scale tunability of the pore size also opens new opportunity to fabricate membranes with on-demand filtration capable of filtering out ions according to their sizes,” said Jijo Abraham of University of Manchester.

Sources: BBC, The Hindu, Nature Nanotechnology

About the Author
  • Kathryn is a curious world-traveller interested in the intersection between nature, culture, history, and people. She has worked for environmental education non-profits and is a Spanish/English interpreter.
You May Also Like
DEC 01, 2019
Earth & The Environment
DEC 01, 2019
Reducing GHG emissions of the transportation sector
The United States Environmental Protection Agency reported that the highest greenhouse gas emissions in 2017 were in the transportation sector, making up a...
DEC 03, 2019
Plants & Animals
DEC 03, 2019
Florida's Manatees Are a Conservation Success Story
Manatees are be a common sight for Floridians who reside close to rivers and other natural waterways, but there was once a time when that wasn’t the...
DEC 08, 2019
Earth & The Environment
DEC 08, 2019
Oilseed rape crops thrive under climate change
Research published recently in Current Biology points towards at least one upside of climate change: some agricultural crops will have longer growing seaso...
DEC 09, 2019
Genetics & Genomics
DEC 09, 2019
Researchers Rewire E. coli to Consume Carbon Dioxide
Milo et. al.   Researchers have genetically rewired the metabolism of Escherichia coli to be autotrophic, using formate (COOH) as a food sou...
DEC 11, 2019
Microbiology
DEC 11, 2019
Ocean Microbes Demonstrate an Evolutionary Principle in Action
Our world is teeming with bacteria and viruses, and in the oceans, their coexistence has them locked in an evolutionary battle....
FEB 13, 2020
Earth & The Environment
FEB 13, 2020
Contamination from Industrial Revolution Discovered in Himalayan Glacier
Scientific studies are revealing just how humans have impacted the environment over the past few centuries. Recently, scientists from Ohio State University...
Loading Comments...