North Carolina State University News Services
Box 7504 Raleigh, NC 27695 (919) 515-3470
Media Contacts:
Dr. Joe DeSimone, 919/962-2166, or [email protected] Tim Lucas, News Services, 919/515-3470, or [email protected]
Brad Lienhart, MiCELL, 919/513-7007, or [email protected]
Dr. Keith Beck, 919/515-6558, or [email protected]
May 28, 1997
Researcher Develops Environmentally Sound CO2 Dry Cleaning
FOR IMMEDIATE RELEASE
Imagine getting your clothes dry-cleaned using carbon dioxide and detergents. There are no toxic dry-cleaning solvents involved, no toxic fumes, and your clothes are as clean as if they'd been cleaned using the traditional process.
You can see it in Las Vegas -- and at North Carolina State University's Centennial Campus.
In the culmination of seven years of research, the world's first carbon-dioxide-compatible detergents will be introduced in Las Vegas at Clean '97, the nation's largest garment care trade show, being held Monday, June 2, through Thursday, June 5. The detergents are the result of research at NC State's College of Engineering, the University of North Carolina at Chapel Hill's Department of Chemistry and, most recently, NC State's College of Textiles.
The detergents, known as surfactants, were invented by Dr. Joseph DeSimone, joint professor of chemical engineering at NC State and chemistry at UNC-Chapel Hill. He also is the co-founder of MiCELL Technologies Inc., located on NC State's Centennial Campus. MiCELL will market the surfactants at Clean '97.
Carbon dioxide, which is taken as a byproduct from other industrial processes, had long been presumed the holy grail of environmentally sound solvents, but it had a seemingly insurmountable problem: its dissolving potential was like water to oil. With the exception of using carbon dioxide to decaffeinate coffee and remove cholesterol from eggs, industry had largely given up on it in the '80s.
But then, with funding from the EPA, the National Science Foundation and a consortium of eight chemical companies, including Dupont and Hoecsht-Celanese, DeSimone discovered a way to give carbon dioxide solvent capacity.
He had been working on another project, using liquid carbon dioxide as a medium for making plastics, when he realized the same methods for that project could be used to dissolve dirt and grease. The development of this patented process resulted in the birth of MiCELL Technologies.
"We've convinced people," said DeSimone. "We've got detergents for CO2."
DeSimone's surfactants will make their world premiere in a prototype pressurized cleaning chamber built by American Dryer Corp. The pressure, 800 pounds per square inch or about half that of a helium tank for party balloons, keeps the carbon dioxide in liquid form.
When the surfactants dissolve in the carbon dioxide they form micelles, a type of molecular cluster which occurs, for example, when soap dissolves in water. The micelles capture the dirt and grease. When the process is over, instead of running the washing fluids down the drain -- or into the air -- the carbon dioxide is reused in the system. The surfactants also are captured after cleaning and recycled.
"We have unequivocally demonstrated that the detergents are effective in cleaning in carbon dioxide," said DeSimone. "This is comparable to having just invented detergent for water today. Just think what you could do with it." The process is now ready to go commercial now, DeSimone says.
More than 30 billion pounds of environmentally noxious organic and halogenated solvents are used each year as cleaning agents, dispersants and industrial processing media, DeSimone says. They could be replaced with carbon dioxide and surfactants. For example, carbon-dioxide-compatible surfactants can clean metal and precision parts, two enormous industrial areas now using massive amounts of water and toxic solvents to meet their cleaning needs.
DeSimone's discovery came at just the right time for the dry-cleaning industry.
The industry, which relies on the toxic solvent perchloroethylene, or "perc," to clean clothes, is facing increasing regulation, higher taxes, and higher insurance rates because of health hazards from its toxic fumes.
"Joe's work with the surfactants could hold the key that will unlock the chemistry to a successful CO2 cleaning system," said Keith Beck, professor of textile chemistry at NC State's College of Textiles. Beck and Dr. Perry Grady, professor of textile engineering, have a grant from the Environmental Protection Agency to evaluate carbon dioxide as a garment cleaning fluid alternative to traditional dry-cleaning solvents.
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NOTE TO EDITORS: Dr. Joe DeSimone can be reached on Saturday, May 31, at the Flamingo Hilton at (702) 733-3111. From June 1-4, DeSimone will be at Bally's Hotel at (702) 739-4111.
MiCELL will hold a press conference at the American Dryer Corp. booth on the show floor on June 2 at 11:30 a.m.
To see a laboratory-size cleaning chamber on Centennial Campus call Tim Lucas at NC State News Services, at (919)733-3111.
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