Catalytic co-cracking of biomass and waste plastics with sawdust mediated ZSM-5 synthesized via activating gel process

Minimizing the catalyst cost is critical to achieving long-term economic feasibility for obtaining bio-chemicals directly from biomass. In the present study, low cost ZSM-5 was synthesized via hydrothermal crystallization of the activated aluminosilicate gel without adding any organic ammonium templates and additional seed crystals. The activation process promoted the depolymerization of the silica-alumina species and the formation of active pasty gel containing nucleation precursors, consequently accelerating the subsequent crystallization re-action. The addition of eucalyptus sawdust (ES) in the synthesis process increased the BET (Brunauer-Emmett-Teller) surface area and acidity of the resultant zeolites. The ES-mediated ZSM-5 (AGZ-10) achieved a higher benzene, toluene, ethylbenzene and xylene (BTEX) carbon yield (18.9 %) from co-cracking of ES and waste plastics (WP) (ES/WP mass ratio at 1:1) at 500 degrees C and exhibited better synergistic effect and anti-coking ability compared to the commercial ZSM-5. The results provide an efficient synthetic strategy to produce low-cost ze-olites, and a promising technique to effectively utilize biomass and plastic wastes.