Catalytic upcycling of waste plastics over nanocellulose derived biochar catalyst for the coupling harvest of hydrogen and liquid fuels

A powerful simple biochar catalyst derived from nanocellulose was applied to the catalytic upcycling of waste plastics into H-2 and liquid fuels for the first time. For the results from model low-density polyethylene (LDPE) py-rolysis, the C-8-C-16 aliphatics and monocyclic aromatics were dominant constitutes of the liquid product with the yields ranging from 22 to 68 wt%. At the temperature of 500 degrees C and biochar to LDPE ratio surpassing 3, the LDPE could be completely degraded into liquid and gas without wax production. A wax yield of 16 wt% was observed at the temperature of 450 degrees C and biochar to LDPE ratio of 4, which was dramatically lower than that (77 wt%) from the absence of biochar at the temperature of 500 degrees C. Up to 92 vol% of H-2 was detected in the gaseous product with a yield of 36 wt%. The lower temperatures and higher biochar to LDPE ratios favored increasing the generation of H-2 at the expense of light gas CnHm especially CH4. Moreover, this biochar catalyst was tested effectively to con-vert the real waste plastics including grocery bags and packaging tray into valuable liquid and H-2-enriched gas. (C) 2021 Elsevier B.V. All rights reserved.