Finding a new source of fresh water is important because not everyone has an access to a clean and safe drinking water. According to the United Nation, about roughly 20 percent of the world’s population, estimated to 1.2 billion people has no access to clean drinking water.
Earth is composed of more than 70 percent water, but 97 percent is undrinkable because of salt content. Drinking seawater is dangerous to a man’s health; it could lead to dehydration and death.
Desalination was used before to filter seawater. It’s a technique that is already employed some parts of the Middle East and the Cayman Islands. However, there were drawbacks to this technique. Ram Devanathan, a researcher at the Energy and Environment Directorate at Pacific Northwest National Laboratory said that the current desalination methods are energy intensive and produce an adverse environmental impact. The energy production consumes large quantities of water and creates wastewater that needs to be treated with further energy input.
Now, a new study released by the journal Nature Nanotechnology early this week talks about a major step in making desalinated water (sea water) safe for drinking. The process involves removing salt from the sea water making it an option as a source of drinking water.
Researchers from the University of Manchester adjusted graphene monoxide membranes, a type of selectively passable membrane that let water pass through while trapping salt ions. It's essentially a molecular filter
Graphite oxide is a compound of carbon, oxygen, and hydrogen in variable ratios, obtained by treating graphite with strong oxidizers.
Graphene oxide membranes are a relatively inexpensive alternative because they are cheaply produced in a laboratory.
Testing showed that when graphene oxide membranes immersed in water on a large-scale, it tends to quickly swell. Once swollen, the membranes do not allow even the water to pass through. Study author Rahul Nair and his colleagues discovered that by placing walls made of epoxy resin on either side of the graphene oxide stops the expansion. The resin restricted the membranes expansion and was able to fine tune their capillary size to prevent any salts from passing through.
It will be tested on an industrial scale to see if the method will hold up. This could be the answer to earth’s drinking water problem if the test is successful.