Sustainable synthesis: High-efficiency ZrO2/KIT-6 catalyst to hydroprocess waste plastics into fuels

Synthetic plastic pollution devastates the environment, human health, biodiversity, and economics of livelihood. Amid various emerging strategies, pyrolysis and subsequent catalytic hydroprocess stand out as promising methods. This upgradation path presents a practical and sustainable approach to transforming plastic waste into valuable resources, and lessening environmental impact. This study aims to produce a higher yield of diesel from mixed plastic trash that satisfies regulatory requirements. The ZrO2/KIT-6 catalyst for hydroprocess accomplished this task and provided the highest yield of chemically equivalent diesel. HDPE, LDPE, and PP waste plastics were independently pyrolyzed using a ZSM-5 catalyst and the pyrolyzed oil of each constituent was mixed to obtain mixed plastic pyrolysis oil. The mixed plastic pyrolysis oil was further upgraded through hydroprocess. Gas chromatography and mass spectroscopy of the obtained fuel revealed a composition comprising aromatics, n-alkanes, and isoalkanes, with each constituent displaying a 95% correlation with commercial diesel. The produced fuel is blended with diesel, followed by comprehensive engine performance assessments to gauge combustion efficiency, overall functionality, and emissions. The evaluation of engine performance outcomes revealed a 93% similarity in emissions. The viability of obtaining clean energy from waste plastics while adhering to legal constraints is presented in this study.