Clean-Up Time: Professor's Invention Pulls Oil From Gulf Waters

Lisa DeJong for The Chronicle

Paul Edmiston, an associate professor of chemistry at the College of Wooster, invented an absorbent material that may help separate oil from water in the Gulf of Mexico.
July 18, 2010

A different kind of water-treatment system may join the fleets of skimmers and other vessels trying to strain oil from the waters of the Gulf of Mexico. Last week, oily Gulf water was dumped onto a new absorbent material developed by a college professor in a test supported by a $200,000 "rapid response" grant from the National Science Foundation.

Though a new cap on the gushing well appeared to have stopped or greatly impeded fresh gouts of oil last week, cleaning up all the crude that has spilled since April is a major challenge.

The new substance—which is like a remarkably powerful sponge as well as a filter—is the brainchild of Paul L. Edmiston, an associate professor of chemistry at the College of Wooster, in Ohio. It looks like a gel but feels like glass, and it goes by the name of Osorb.

Mr. Edmiston compares its ability to swell to Goldilocks's perfect porridge. Its level of rigidity is just right, not too hard and not too flexible, he says. It can shrink and expand without cracking. Its structure can store an enormous amount of tension—in fact, the material can lift up to 20 times its weight, he says.

Another thing it does really well, though, is absorb hydrocarbons—like oil—while leaving behind water, proteins, genetic material, and inorganic salts, Mr. Edmiston says. And it has advantages compared with other kinds of filters. "The materials that Paul has cost less and soak up more," says Mark A. Shannon, a professor of mechanical engineering at the University of Illinois at Urbana-Champaign and director of a National Science Foundation center focused on water-purification systems.

Mr. Edmiston came up with the material in 2005, and five years later, he is the chief science officer of a rapidly growing company that has set out to clean up the past century's environmental messes.

The group, Absorbent Materials Company LLC, was hired by British Petroleum in May 2009 to develop a process for cleaning "produced water," a byproduct of onshore and offshore drilling that usually contains oil, inorganic salts, rock dust, and chemicals from the oil-extraction process. One attraction from the oil company's perspective: By using Osorb, oil dispersed in this water could be collected and recovered.

The current test is not on produced water, but to see if a device with Osorb can clean 2,200 gallons of water contaminated with high levels of crude oil—Gulf oil-spill conditions.

The cleaning machine has four metal containers that hold Osorb. Polluted water flows in through the top of the containers, where it meets the material. Clean water then flows from the bottom. The containers have to be reset regularly to remove oil from the material after it has reached its capacity.

There are other ways to separate oil from Gulf water, according to Berrin Tansel, a professor of civil and environmental engineering at Florida International University. A spinning centrifuge, for instance, can separate the two. Another method is to dissolve air in water under high pressure. The pressurized air forms bubbles, which force oil droplets away from the water, says Ms. Tansel, whose team recently received an NSF rapid-response grant to study the Gulf's emulsions.

A Recipe for Success

Mr. Edmiston calls Osorb "swellable organically modified silica" in scientific papers, though he swaps that for "swellable glass" in conversation. The recipe is simple enough, he says. Start with a container of solvent, such as acetone. Put in molecules containing silicon that come together and form the final product, a large silica-based "macromolecule." Add a solution of water and fluoride ions, and stir.

The trick to its absorbency is in the way those building-block molecules are arranged. The structure consists of outer parts that repel water, preventing it from being absorbed, but that allow hydrocarbons in. The interior has a multitude of tiny pores that can hold the hydrocarbons.

After stumbling upon the substance in his laboratory, the researcher set out to find out how and why glass could absorb oil and how to scale up the process of production. In late 2008, he founded the company, now called ABSMaterials.

At the end of 2009, the privately held company was valued at $6.9-million, says Stephen R. Spoonamore, its chief executive. One patent has been approved, and 17 others are pending, according to Mr. Spoonamore.

Mr. Edmiston believes that being at Wooster, a small liberal-arts college in Ohio, was invaluable to Osorb's development. He had no competition during the years he spent studying the material, and he attributes that to Wooster's low profile—it doesn't have a reputation as a hotbed of chemistry innovation.

He also thinks Ohio's manufacturing industry is an asset that provided the base he needed to begin producing Osorb. He doesn't think what he has achieved would have been possible somewhere else.

In the future, Mr. Edmiston wants his company to be a source of high-tech jobs for the region, an incentive for young college graduates to stay in the state. "I'd like to reverse the Ohio brain drain," he says. He's made a small start: Three of the company's 28 employees are Mr. Edmiston's former students and Wooster graduates.

After 14 hours of testing last week, the company's machine seemed like a cautious success. It recovered six barrels of crude oil and left the water clean enough to return to the ocean. The team's next challenge is learning how to scale up: engineering its systems to clean more water more quickly, in order to keep up with the large amounts of oil that have been dumped into the Gulf.