Chemical upcycling of polyolefin plastic waste to lubricant, wax and fuel-range hydrocarbons over metal-based catalysts is a crucial technological solution to the enormous environmental threat posed by plastic waste. However, currently available methods are incompatible with chlorine-contaminated feedstocks. This paper reports a two-stage strategy for upcycling chlorine-contaminated polypropylene. The first stage uses magnesia-alumina mixed oxide to trap chlorine, enabling the upcycling of plastic waste with up to 10% polyvinyl chloride content to lubricants over ruthenium-based catalysts in the second stage. The strategy eliminates HCl emissions and chlorine contamination in products.

Pavel A. Kots, Brandon C. Vance, Caitlin M. Quinn, Cong Wang, Dionisios G. Vlachos