Photothermal Upcycling of Waste Polyvinyl Chloride Plastics.

Abstract

Upgrading the most difficult-to-recycle waste polyvinyl chloride remains a significant challenge due to the potential formation of highly toxic substances, such as polychlorinated biphenyls. Here, we introduce a paradigm shift with a mild photothermal dechlorination-carbonization process that converts waste polyvinyl chloride plastics into valuable carbon materials. Through detailed techno-economic assessment (TEA) process modeling, based on recycling 96,000 tons of plastics, we demonstrate that utilizing clean solar energy for photothermal conversion can save approximately 2.34 × 10¹² kJ electricity and reduce the carbon footprint by 261,912.2 tons compared to traditional thermal-driven methods, offering clear environmental benefits. Notably, this photothermal recycling method can process more than 10 types of postconsumer and mixed waste polyvinyl chloride plastics, yielding carbon materials that exhibit excellent performance as components in sodium-ion energy storage batteries. Photothermal catalytic recycling of plastics thus emerges as a green and sustainable technology with promising applications.