"Our strategy is to create a driving force for recycling by converting polyolefin waste into a wide range of valuable products, including polymers, naphtha, or clean fuels," said Linda Wang, the Maxine Spencer Nichols Professor in the Davidson School of Chemical Engineering at Purdue University. "Our conversion technology has the potential to boost the profits of the recycling industry and shrink the world's plastic waste stock." Initial results of Wang's study were published Jan. 29 in ACS Sustainable Chemistry and Engineering.
The conversion process uses selective extraction and hydrothermal liquefaction to convert wet biomass into a crude-like oil compound under moderate temperature and high pressure. Once the plastic is converted into naphtha, it can be further separated into specialty solvents or other products. The clean fuels derived from the polyolefin waste generated each year can satisfy 4 percent of the annual demand for gasoline or diesel fuels.
"Plastic waste disposal, whether recycled or thrown away, does not mean the end of the story," Wang said. "These plastics degrade slowly and release toxic microplastics and chemicals into the land and the water. This is a catastrophe, because once these pollutants are in the oceans, they are impossible to retrieve completely."
Wang hopes her technology will encourage the recycling industry to increase their efforts at reducing the rapidly rising amount of plastic waste. She and her team are looking for investors or partners to assist with demonstrating this technology at a commercial scale.