Plastic waste gasification for clean H2- and CO-rich syngas production: Recent advances, industrial challenges, and future directions

The rapid growth of global plastic production and consumption, coupled with low recycling rates and escalating environmental concerns, has created an urgent need for sustainable plastic waste valorization technologies. Thermochemical gasification has emerged as a promising and potentially scalable approach for converting plastic waste into H 2 - and CO-rich syngas, thereby enabling clean energy generation and circular resource recovery. This review critically examines recent advances in plastic gasification, with particular emphasis on feedstock physicochemical properties, reaction mechanisms, and the process variables that govern syngas yield and composition, including temperature, residence time, pressure, gasifying agents, reactor configurations, catalyst systems, and co-gasification strategies. It further highlights the major barriers to industrial implementation, such as feedstock heterogeneity, HCl release from PVC, tar formation, catalyst deactivation, and the high cost of syngas purification. Emerging directions, including advanced catalyst design, multi-feedstock co-gasification, process intensification, and integration with renewable hydrogen and carbon capture technologies, are also discussed as potential pathways toward more efficient and sustainable systems. In addition, greater incorporation of techno-economic assessment and life-cycle analysis is needed to support the sustainable deployment of plastic gasification. This review provides an integrated process-to-application perspective for evaluating plastic gasification from process performance to downstream H 2 /CO-rich syngas utilization.