Cu Decorated Rh/TiO₂ Catalyst for Selective Hydrogenation of Phenylacetylene to Styrene

Abstract

Phenylacetylene as an impurity in styrene is poisonous to catalysts for styrene polymerization in the production of polystyrene plastics. The selective hydrogenation of phenylacetylene to styrene is an industrially promising route to overcome this challenge yet lacks cost‐effective catalysts to prevent the overhydrogenation of styrene to ethylbenzene. In this work, we report an efficient and robust copper‐decorated Rh/TiO2 catalyst for the selective hydrogenation of phenylacetylene to styrene. By optimizing the copper coverage on TiO2 supported Rh nanoparticles, we achieved a selectivity of 83% towards styrene formation at a phenylacetylene conversion of 93%. The appropriate Cu coverage is found to modulate the electronic states of surface Rh atoms and changes the Rh exposed active sites, weakening the binding strength of alkene and hydrogen intermediates on Rh and thus mitigating the overhydrogenation and enhancing the selectivity for styrene generation. This work offers insights on the rational design of efficient Rh‐based bimetallic catalysts for selective hydrogenation of phenylacetylene to styrene.