Solvent‐Free Heterogeneous Catalytic Hydrogenation of Polyesters to Diols

The utilization of carbon resources stored in plastic polymers through chemical recycling and upcycling is a promising approach for mitigating plastic waste. However, most current methods for upcycling suffer from limited selectivity towards a specific valuable product, particularly when attempting full conversion of the plastic. We present a highly selective reaction route for transforming polylactic acid (PLA) into 1,2‐propanediol utilizing a Zn‐modified Cu catalyst. This reaction exhibits excellent reactivity (0.65 g gcat−1 h−1) and selectivity (99.5 %) towards 1,2‐propanediol, and most importantly, can be performed in a solvent‐free mode. Significantly, the overall solvent‐free reaction is an atom‐economical reaction with all the atoms in reactants (PLA and H2) fixed into the final product (1,2‐propanediol), eliminating the need for a separation process. This method provides an innovative and economically viable solution for upgrading polyesters to produce high‐purity products under mild conditions with optimal atom utilization.