Catalytic Copyrolysis of Cellulose and Thermoplastics over HZSM-5 and HY

Abstract

Catalytic pyrolysis with HZSM-5 is a promising method for the production of renewable aromatic hydrocarbons directly from biomass, even though the aromatic yields are still very low. Recent studies have shown that cofeeding of biomass with plastic significantly improves the aromatic yield due to high hydrogen content in plastic. In an effort to determine the influence of the zeolite pore size and the molecular diameter of cofeeding plastic on the aromatic production, catalytic copyrolysis of cellulose and thermoplastics, including random polypropylene (PP) and linear low density polyethylene (LLDPE) was conducted over HZSM-5 and HY catalysts. Thermogravimetric (TG) results showed that maximum decomposition temperature of PP was shifted to the higher temperature when PP was copyrolyzed with cellulose over HZSM-5 because the diffusion of PP molecules was hindered by the cellulose-derived coke and char. This hindering effect was attenuated by employing LLDPE as the cofeeding plastic due to its smaller molecu...