Highly active and selective heterogeneous Ru/La2O3-CeO2 catalyst for hydrogenolysis of LDPE to valuable chemicals

Catalytic upcycling of polyolefin waste to valuable chemicals via hydrogenolysis is a promising strategy; however, developing Ru-based catalysts with low gas selectivity without compromising catalytic activity for the hydrogenolysis of polyethylene remains a significant challenge. Herein, we demonstrate that incorporating strong base sites into the support can suppress gas product formation while maintaining high activity in the hydrogenolysis of LDPE. La 2 O 3 -modified CeO 2 -supported Ru (Ru/La 2 O 3 -CeO 2 ) served as a highly active heterogeneous catalyst, effectively mitigating gas production (yield: 5.1%, CH 4 2.5%) and providing valuable liquid chemicals and waxes with a high yield of 95% at 513 K. Furthermore, at 523 K, the catalyst achieved both low gas selectivity (5.0%) and a high reaction rate of 16.8 g reacted PE g catalyst −1 h −1 at 99% conversion. Comprehensive characterization (including H 2 -TPR, XRD, TEM, XAS, CO 2 -TPD and XPS) revealed that the La 2 O 3 modified CeO 2 generated strong base sites, which reduced Ru particle size via metal-support interactions. These smaller Ru particles suppressed the consecutive C C bond cleavage of LDPE, thereby significantly inhibiting CH 4 formation. This work highlights the pivotal role of support basicity in tuning metal particle size for selective polyolefin upcycling.