Research progress in the co-pyrolysis of renewable biomass with plastic wastes for the synergetic production of chemicals and biofuels: A review

Abstract

The quantity of plastic waste generated by the public has increased dramatically over the years. Biomass is an abundant and substantial energy resource found in diverse forms all over the planet. In this regard, the co-pyrolysis of plastic and biomass wastes is an attractive option to mitigate the issue of waste accumulation and viable fuel production. This review focuses on progress in waste disposal and energy generation through co-pyrolysis. The properties of common solid feedstock combinations are addressed with an emphasis on proximate analysis, elemental composition, and heating value. Subsequently, state-of-the-art kinetics is reviewed and compared for the efficacies of various kinetic models, which could be applied to understand decomposition mechanisms. The synergy between biomass and plastics was analyzed, and the impact of decomposition mechanisms on the bio-oil, char, and gas yield and composition was discussed. In addition, this study unveiled various reaction pathways for non-catalytic and catalytic co-pyrolysis. Finally, a summary of the economics in co-pyrolysis with knowledge gaps concerning waste management and energy production is addressed. The main goal of this review is to provide a feasible, practical pathway for clean and effective plastic waste disposal by using biomass waste to increase the synergistic effect.