Low-temperature catalytic upgrading of waste polyolefinic plastics into liquid fuels and waxes

Abstract

A new low-temperature catalytic upgrading of waste polyolefinic plastics to valuable chemicals such as liquid fuels and waxes by a heterogeneous catalyst is presented. CeO2-supported Ru (Ru/CeO2) acted as an effective and reusable heterogeneous catalyst, showing much higher activity than other metal-supported catalysts in hydrogenolysis of low-density polyethylene, and the catalyst worked even under mild reaction conditions such as low temperature of 473 K and low H2 pressure of 2 MPa, providing liquid fuel (C5-C21) and wax (C22-C45) in 77 % and 15 % yields (total 92 % yield), respectively. This catalyst was applicable to hydrogenolysis of various low-density polyethylenes, high-density polyethylene, polypropylene to provide the valuable chemicals (liquid fuel + wax) in high yields (83–90 %). Furthermore, a commercial plastic bag and waste polyethylenes could be transformed to the valuable chemicals in high yields (91 % and 88 % yields).