The conversion process produces significantly more energy than it consumes and results in transportation fuels such as diesel that can be blended with existing ultra-low-sulfur diesels and biodiesels, scientists at the University of Illinois at Urbana-Champaign said Thursday.
Other products such as natural gas, solvents, gasoline, waxes and lubricating oils also can be obtained from shopping bags, they said.
The technique, which involves heating the bags in an oxygen-free chamber in a process called pyrolysis, is very efficient, researcher leader Brajendra Kumar Sharma said.
"You can get only 50 to 55 percent fuel from the distillation of petroleum crude oil," he said. "But since this plastic is made from petroleum in the first place, we can recover almost 80 percent fuel from it through distillation."
Previous studies have used pyrolysis to convert plastic bags into crude oil, but Sharma's team took the research further by converting the crude oil into different petroleum products.
Americans throw away about 100 billion plastic shopping bags annually, the Worldwatch Institute says, while the U.S. Environmental Protection Agency reports only about 13 percent are recycled.