Work

Self-driven tandem alcoholysis for full upcycling of waste polycarbonate plastics

Year: 2026

Type: article

Abstract: Conventional alcoholysis processes for polycarbonate (PC) recycling require excess methanol input, high reaction temperatures and complicated downstream product separation steps, severely limiting environmental and economic sustainability. Here we report a facile, self-driven tandem alcoholysis process to address these challenges. Methanol-based PC alcoholysis reaction is coupled to a downstream glycerol transesterification step to rapidly convert the dimethyl carbonate intermediate into methanol, thus forming a closed-loop methanol flow to boost the overall reactions. Additionally, the reactions are catalyzed by eggshell-derived multimetallic CaO, which provides abundant acid-base sites for synergistically deprotonating alcohols and activating ester bonds to facilitate a selective conversion. This integrated design not only enables 98.8% less methanol usage and significantly lower reaction temperature than the PC-alone alcoholysis process (80 °C versus >130 °C), but also generates bisphenol A (96% yield) and 5-hydroxymethyl-1,3-dioxolan-2-one (90% yield) as higher-value products. The process is adaptable to treating mixed-plastic feeds with robust performance. The pilot-scale trials (>5 kg) using real mixed plastic waste demonstrate superior upcycling performance and distinctly improved environmental and economic benefits over the existing industrial synthesis routes. Overall, this scalable, self-driven tandem alcoholysis process offers a sustainable, industrially-viable platform for upcycling PC-containing waste plastics.

Source: Nature Communications

DOI: 10.1038/s41467-026-71261-x