Researchers from Mexico’s Purdue University, the Technological University of Queretaro, and the Engineering and Industrial Development Centre have found a way to convert post-consumer LDPE and HDPE into energy-storing carbon that can be used in batteries.
According to the American Chemical Society (ACS), the scientists found a way to recycle plastic bags into carbon chips that can be used as anodes in lithium-ion batteries.
In their process, they immersed PE bags in sulfuric acid, sealed them inside a reactor and heated the sample to just below PE’s melting point. This caused sulfonic acid groups to be added, which allowed the plastic to be heated to much higher temperatures without vaporising hazardous gases.
The scientists then removed the sulfonated PE from the reactor and heated it in a furnace at 1,600 degrees Fahrenheit to produce pure carbon. The carbon is then ground into black powder and used to make anodes for batteries.
The novel process is described as more efficient than prior approaches to converting PE into pure carbon.
“The resulting batteries performed comparably to commercial batteries,” according to the ACS’ research paper, published in ACS Omega.
“On the basis of the literature survey, this is the first report which demonstrates that a solvothermal sulfonation process followed by thermal treatment successfully converts waste LDPE and HDPE plastic bags to functional energy-storing carbons.”