Removing Salt To Relieve The World’s Thirst

97 percent of water on Earth is salt water. What if we could drink it?

By leveraging electricity rather than force, Kyle Knust, a 26-year-old doctoral student in analytical chemistry at the University of Texas at Austin, created an energy-efficient way to separate salt from saltwater with an electric current. His device is called the Waterchip (it’s small enough to fit in the palm of a hand), and water flows through it along a Y-shaped microchannel. An electrode emits a charge where the Y splits, creating an electric field that deflects the salt down one branch of the channel as highly concentrated brine. Desalinated water runs out the other arm. Tony Frudakis, CEO of Okeanos, a Cincinnati-area start-up, licensed the device. A single Waterchip removes about 25 percent of the salt from seawater and produces a mere trickle. “The technology is infinitely scalable,” he says. Running a few Waterchips in a series could make the output progressively purer, and running millions in parallel could theoretically produce as much freshwater as any giant reverse-osmosis plant—and consume half the energy. via