A statement was released recently claiming that within two generations the general population will be struggling with massive water shortages, so chemists are looking to the seas for a new supply.
The research team created a method for removing salt from water using small electrical fields, according to a University of Texas press release.
The new system, called electrochemically mediated seawater desalination, is very low-energy and able to run on a simple store-bought battery. It eliminates the high-energy waste of past methods and doesn't need a membrane to serve its function.
"The availability of water for drinking and crop irrigation is one of the most basic requirements for maintaining and improving human health," said Richard Crooks of The University of Texas at Austin. "Seawater desalination is one way to address this need, but most current methods for desalinating water rely on expensive and easily contaminated membranes.
"The membrane-free method we've developed still needs to be refined and scaled up, but if we can succeed at that, then one day it might be possible to provide fresh water on a massive scale using a simple, even portable, system," he said.
We don't have to wait for the world's fresh water to run dry to put this technology to good use. About a third of the planet is already thirsty and living in water-stressed areas.
"People are dying because of a lack of freshwater," Tony Frudakis, founder and CEO of Okeanos Technologies said. "And they'll continue to do so until there is some kind of breakthrough, and that is what we are hoping our technology will represent."
In order to desalinize the water, the researchers apply three volts of electricity a plastic chip filled with salty water. There's a microchannel with two branches inside of the chip. At the channel's junction an electrode neutralizes a portion of the chloride ions to create an "ion depletion zone" which increases the electric field. The field redirects the salt into one branch of the microchannel, removing it from the water.
"The neutralization reaction occurring at the electrode is key to removing the salts in seawater," said Kyle Knust, first author of the paper. "This was a proof of principle. We've made comparable performance improvements while developing other applications based on the formation of an ion depletion zone. That suggests that 99 percent desalination is not beyond our reach."
The only problem is the current size of the device, a much larger system would have to be built in order to provide water to a group of people. The researchers are confident this can be accomplished.
"You could build a disaster relief array or a municipal-scale unit," Frudakis said. "Okeanos has even contemplated building a small system that would look like a Coke machine and would operate in a standalone fashion to produce enough water for a small village."