Highly efficient recycling of polyester wastes to diols using Ru and Mo dual-atom catalyst

The chemical recycling of polyester wastes is of great significance for sustainable development, providing access to oxygen-containing chemicals but typically suffering from low efficiency or separation difficulties. Here we report anatase TiO2 supported Ru and Mo dual-atom catalysts that convert various polyesters to corresponding diols with 100% selectivity via hydrolysis followed by hydrogenation in water under mild conditions (e.g., 160 °C, 4 MPa H2). Microscopy evidences coexistence of Ru single-atom and O-bridged Ru–Mo dual-atom sites. Ru single-atom sites activate H2 for hydrogenation of carboxylic acids derived from polyester hydrolysis, while O-bridged Ru–Mo sites suppress hydrodeoxygenation of resultant alcohols due to a high reaction energy barrier. The dual-atom catalysts can be regenerated with high activity and stability. This work provides an effective approach to reconstruct polyester wastes into valuable diols with promising application potential.

Minhao Tang, Ji Shen, Yiding Wang, Yanfei Zhao, Tao Gan, Xusheng Zheng, Dingsheng Wang, Buxing Han, Zhimin Liu