UT research team creates way to take salt out of water


by ANDREW CHUNG and Photojournalist JOHN FISHER

KVUE News Austin

Posted on July 19, 2013 at 12:45 PM

AUSTIN -- Finding drinking water is a problem worldwide, so imagine taking salt water from the Gulf of Mexico and turning it into fresh water for Central Texas. One University of Texas professor and his research team are working on a new technology that could make the process much easier.

"I think one of the things that's so unique about this technology is simplicity," said UT graduate chemistry student Kyle Knust.

The tiny device, with the help of two AA batteries, creates an electric field that separates salt from water.

Richard Crooks, PhD. is Knust's chemistry professor. So far their team has been able to remove about 25 percent of the salt.

"To make fresh water from sea water, you need to remove about 99 percent of the salt from the water," Crooks said.

A microscope shows the process, which includes a Y-shaped channel that's no thicker than the size of a human hair. An electrode creates the electric field. The seawater can be seen in the lab, flowing from right to left on a screen. When Knust turns the device on, the electric field shunts the salt into the upper channel. The desalinated water flows into the lower channel.

Today's desalination plants have one thing in common. They pump seawater at high pressure through special membranes to remove salt. However, that seawater can contain microscopic organisms.

"The problem is, there's a very thin membrane, and they begin growing on the membrane, and they destroy the membrane," Crooks said.

Crooks says these membranes are very expensive. His team's technology eliminates the membrane.

While their device is small, it could, in the future, be built on a huge scale.

"But we're a long, long way. You know, this is a basic technology developed here at UT, and we applied for a patent. That patent has been licensed by a company, and the company right now is trying to develop it," Crooks said.

Given the water woes in Texas, we would have an advantage.

"There's plenty of water down in the Gulf," Crooks said.

If the idea works, it could help solve our quest for fresh water.