Water Warriors

Scientist Sidney Loeb's work at UCLA in the early 1960s gave birth to the process known as reverse-osmosis desalination, which is today a multi-billion-dollar, world-wide industry. Loeb is pictured in Boelter Hall with an early desalination machine known as "the big dripper" for its paltry output of freshwater.

Copyright © Courtesy of the Henry Samueli School of Engineering and Applied Science

The Water Warriors

A professor of chemical engineering, Cohen was born in Israel and moved with his family to Canada at age 15. He did his doctoral work in polymer science and fluid mechanics at the University of Delaware. As a researcher and a human being, Cohen is mostly fearless. Solid as a linebacker even in middle age, he is a fifth-degree black belt and internationally known teacher of Shotokan karate, which he has studied since his teens. When he teaches karate, Cohen will look a student straight in the eye and say: "Go ahead and punch me as hard as you can." In science, if another researcher warns him, 'That won't work,' Cohen might try it anyway.

Cohen started the Water Technology Research Center, or WaTeR Center, last year with two colleagues in the Civil and Environmental Engineering Department, Julius "Bud" Glater, 85, an adjunct professor emeritus, and Eric Hoek, 34, an assistant professor. The WaTeR Center is a multidisciplinary effort with laboratories housed at the Henry Samueli School of Engineering and Applied Science.

Glater's involvement with desalination goes back to the Kennedy Administration, when the rallying cry to American scientists was, "Put a man on the moon and make the desert bloom." Though retired, Glater reports three or four days a week to his office in Boelter Hall, where he advises doctoral students, answers e-mail, and talks membrane science with Cohen, whom he describes as "one of the most brilliant guys I've ever worked with. He's got the energy of a 16-year-old — only he's focused!"

Hoek, who is from New Jersey, cared more about sports than academics in high school. But during an internship with the pharmaceutical giant Merck & Co. in college, he got turned on by chemical engineering. At UCLA, Hoek is exploring the next frontier of RO desalination, using nano technology to create membranes that are more efficient and use less energy. Hoek relishes the freedom that academia affords to explore uncharted territory and to seek answers to questions that no one else is even asking. "Sometimes," he says, "it's just too much fun."

The WaTeR Center got off the ground with $1 million from Proposition 50, the California clean water act, and another $1.6 million from private industry and other donors. The center's reach extends far beyond UCLA. Cohen, Glater and Hoek collaborate with researchers from other UC campuses as well as universities in the United States and abroad, major membrane manufacturers like Koch Membrane Systems and Hydranautics, and government agencies, among them the Metropolitan Water District of Southern California and the state Department of Water Resources.

Science for a Thirsty World

RO desalination uses extremely high pressure to force seawater or brackish water, which refers to high-salinity rivers and groundwater, through the pores of a semipermeable membrane. The pores are about one ten-thousandth of a micron — almost unfathomably small when you consider that a human hair is 50 microns in diameter. Water molecules under pressure can pass through these pores but not salt ions or other impurities, like bacteria.

Cohen, Hoek and Glater are working to minimize or eliminate the impediments to widespread use of RO desalination. The technology has been around for decades, but its major shortcoming is cost. The process requires huge amounts of electricity to force water through the membrane. Another big problem is so-called fouling and scaling, which is what happens when mineral salts, bacteria and other gunk collect on the membrane's surface and clog pores. Scaling puts higher energy demands on the system and leads to costly cleanup and replacement of membranes.

Published Jul 1, 2006 12:00 AM