Chemists work to desalt the ocean for drinking water, one nanoliter at a time

University of Texas at Austin: By creating a small electrical field that removes salts from seawater, chemists at The University of Texas at Austin and the University of Marburg in Germany have introduced a new method for the desalination of seawater that consumes less energy and is dramatically simpler than conventional techniques. The new method requires so little energy that it can run on a store-bought battery.

The process evades the problems confronting current desalination methods by eliminating the need for a membrane and by separating salt from water at a microscale.

The technique, called electrochemically mediated seawater desalination, was described last week in the journal Angewandte Chemie. The research team was led by Richard Crooks of The University of Texas at Austin and Ulrich Tallarek of the University of Marburg. It’s patent-pending and is in commercial development by startup company Okeanos Technologies.

“The availability of water for drinking and crop irrigation is one of the most basic requirements for maintaining and improving human health,” said Crooks, the Robert A. Welch Chair in Chemistry in the College of Natural Sciences. “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.”

This new method holds particular promise for the water-stressed areas in which about a third of the planet’s inhabitants live. Many of these regions have access to abundant seawater but not to the energy infrastructure or money necessary to desalt water using conventional technology. As a result, millions of deaths per year in these regions are attributed to water-related causes....

A prototype "water chip" developed by researchers at The University of Texas at Austin in collaboration with a startup company. From the UT Austin website