by Bennett Davis
Perfluoroalkyl substances, a family of more than 5,000 “forever” industrial chemicals, have widely contaminated U.S. water supplies (see Trends Journal, 28 January 2020). Some are known to cause cancer; little research has been done on the health effects of most of them.
The only ways to get rid of PFAS have been to filter them out of water and then burn them, using large amounts of energy.
Now, thanks to work at Drexel and Clarkson universities, there’s a new way to break up PFAS: blast them with plasma.
Plasma is considered the fourth state of matter, along with solids, liquids, and gases. It’s created by putting heat or electricity into a gas.
The key to turning PFAS into less toxic compounds is to break the strong bond holding its carbon and fluorine atoms together. When Drexel researchers blasted PFAS with a hot plasma using plain air, about a quarter of those bonds broke.
Also, the plasma blasts work with far less energy than incineration and without adding new chemicals to the mix and without making additional harmful byproducts.
Experiments using different gases may produce more powerful results.
Clarkson scientists tested a plasma decontamination method on groundwater samples taken from Wright Patterson Air Force Base. (Military bases are notorious PFAS contamination sites.) The method reduced PFAS contamination level below the health limit of 70 parts per trillion that the U.S. Environmental Protection Agency has proposed.
TRENDPOST: As the world continues to run short of fresh water, more attention will be devoted to finding and funding new ways to clean contaminated water. A new service sector will grow as a result.
by Bennett Davis