Unlocking green potential: Enhancing biomass valorization via thermal depolymerization with spent catalysts

Effective catalysts for the thermal depolymerization of biomass present an attractive way to reduce energy consumption. This study investigated the effect of spent ZSM-5 catalysts on product distribution through thermal catalytic depolymerization. The spent catalyst has similar properties to the commercial fresh catalysts, as assessed through characterization analysis. The utilization of spent catalysts can enhance the production of bio-oil. The bio-oil yields for rice straw, brown solid, alkaline, and dealkaline lignin by catalytic depolymerization are 11%, 31%, 6%, and 21%, respectively. Therefore, depolymerization using a spent catalyst is a promising method to degrade lignocellulose.