What's super-absorbent and can clean up nasty spills? Wringable, washable and can be reused again and again? It's called Osorb, and it's a kind of ShamWow for industrial accidents. Mix it with dirty water and watch it magically absorb oil, pesticides and organic volatile compounds!
Okay, so Osorb may not be a miracle product. But, as we saw demonstrated in yesterday's live webcast, it is pretty cool. Chemical engineer Paul Edmiston, Osorb's creator, accepted a bottle of fuel additive from an NSF employee and used it to liberally spike a bottle of clean water. He then poured a white powder into the cocktail of jet fuel and detergents and shook it; when a foamy orange substance grew at the surface, he filtered the water into a clear glass and casually pounded it back.
So what, exactly, is it that allowed him to drink from an oil slick and live to tell about it? A sponge made from a silicon and benzene polymer. Chemically, "it's halfway between the window-pane glass of your car and the caulk in your bathtub," Edmiston says.
When Osorb comes into contact with oil or other water-hating (nonpolar) chemicals, such as oils, fats and other hydrocarbons, its stacks of benzene-silicon plates expand like an accordion to absorb the contaminants. Each gram of material can hold up to eight times its own weight. Because electrically charged liquids, like water, don't interact with Osorb, the contaminated material can easily be filtered out of it, making Osorb an ideal candidate for cleaning up all kinds of water pollution.
Edmiston originally created the silica substance for an entirely different purpose: to detect explosives in airports. One day, a student in his lab at the College of Wooster accidentally spilled some acetone into a beaker filled with it. As he watched the white powder swell with the chemical, Edmiston realized he could expand its potential uses. Since then, Osorb has been pilot-tested for cleaning up environmental hazards, including last summer's oil spill in the Gulf of Mexico.
Working along the Gulf's shoreline, Edmiston used two funnel-shaped vortex tanks on the back of a truck as the base for his water-cleaning operation. In this two-tank system, Osorb and polluted water go into the first tank where they are swirled around, so that the Osorb particles thoroughly mix with organic contaminants, such as oil and methane. The filtered water can be returned to the environment, and the oil-soaked material is moved to the second tank, where it's heated and chemically treated to release the contaminants. The chemicals can then be separated and, as in the case of petroleum, reused or properly disposed of. After a quick rinse, Osorb goes back in the first tank to be reused.
While labor intensive, using Osorb to clean water is faster than waiting for bacteria or other natural processes to get rid of oil, and, unlike dispersants, it's not a toxic chemical that remains in the water. Because natural organics, like proteins and carbohydrates, tend to be more charged than synthetic ones, Edmiston says there is little chance that Osorb would remove good chemicals from the environment.
Future potential uses for Osorb include remediating Superfund sites, cleaning pesticides from soil, and removing contaminants from the air. The material was only in the beginning stages of development during last year's oil spill, so Edmiston's team wasn't quite ready to mass-produce it for the cleanup effort. But, he says, "I think we'll be ready for the next time."