A porous media catalyst for waste polyethylene pyrolysis in a continuous feeding reactor

This study investigated the catalytic pyrolysis of waste polyethylene (PE) using a ZSM-5/Al2O3 porous media catalyst in a continuous feeding mode. The findings revealed that the porous media catalyst with 100 mm height and 40 PPI (pore per inch) pore size had the supreme catalytic performance, which could obtain the highest pyrolysis oil yield and the light fraction (<C12) and aromatics in the oil, and improve the catalytic stability of the porous media catalyst. The optimal operating conditions were the pyrolysis temperature of 460 degrees C, the carrier gas velocity of 65 mL/min, and the plastic feeding rate of 25 g/h, of which the light fraction and aromatics in the oil were up to 95.25 % and 97.33 %. Moreover, the catalytic cycling performance of the porous media catalyst was thoroughly investigated. The catalytic activity declined and the catalyst deactivation rate decreased after multiple regeneration cycles. This study presents a comprehensive investigation of waste PE catalytic cracking using the porous media catalyst in continuous feeding mode, which can provide insightful guidance on the industrialization of plastic waste valorization.