Researchers Are This Close To Making Cheap, Portable Desalinization Real

It’s no secret that our freshwater sources are depleting quickly, and we’re all basically fucked unless we can find some way to either slow down the process or manually create more. Fortunately, chemists at the University of Texas at Austin and the University of Marburg in Germany might be able to accomplish the latter.

In 20 years, almost 50 percent of the world’s population will live in areas of water scarcity. Although the world population, estimated to grow to over nine billion by 2050, could use some more freshwater as a whole, desalination—the process of removing the salt from seawater—could be most helpful in areas with lots of saltwater and little drinking water.

Several desalination plants have popped up in parts of the world like the Gaza strip and have successfully provided drinking water to about 20 percent of its population, but the plants require special filters and a large amount of energy, which come at a high price. In an effort to confront these costly challenges, a pair are researchers are introducing a method that consumes less energy (it can run solely on a store-bought battery) and is simple compared to other methods.

The patent-pending project is spearheaded by Richard Crooks of the University of Texas at Austin and Ulrich Tallarek of the University of Marburg. The new technique, called electrochemically mediated seawater desalination, involves a plastic chip filled with saltwater that contains a microchannel with two branches. As described in the press release, an embedded electrode neutralizes some of the chloride ions in the water, resulting in an ion depletion zone that increases the local electric field. The change in the electric field pushes the salt into one branch and desalinated water through the other. Simply put: an electric field change in the chip’s tiny channels pulls the salt away from water, and the ion depletion zone doesn’t allow the salt to penetrate the freshwater channel.

“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 freshwater on a massive scale using a simple, even portable, system,” Crooks said in a statement.

The process has made possible 25 percent desalination so far, but drinking water requires 99 percent desalination. The team is also trying to put the process on a larger scale, since the method currently produces 40 nanoliters of desalted water per minute. It’s a long way from finished, but at least it’s a start