Chlorine Radical Mediated Tandem Dehydrogenation-Oxidation for Upcycling Polyolefins to Functional Wax at Low Temperature in Air.

Abstract

Polyolefins valued for their excellent properties are the highest produced and widely used plastics. However, their chemical stability and massive accumulation arouse severe environmental issues, necessitating urgent resolution of recycling. Current recycling strategies encounter challenges like noble metal catalyst dependence, harsh conditions, sensitivity, poor selectivity, and low-valued products. Here, we report a potentially sustainable and scalable tandem dehydrogenation-oxidation system that operates under mild conditions (120 °C, in air) without precious metals. With 1,1,2-C2H3Cl3 serving as both the solvent and chlorine radical source, polyolefins, and mixed polyethylene wastes can be efficiently converted into α,ω-functional wax under the combined action of H2O2 and phase-transfer catalyst (CP)3PW4O16 with >95% carbon utilization efficiency. The process is tolerant to water, oxygen, and common plastic additives, eliminating pre‑purification. This work offers an economically promising and potentially scalable pathway for polyolefin waste upcycling.