Continuous Flow Liquid-Phase Semihydrogenation of Phenylacetylene over Pd Nanoparticles Supported on UiO-66(Hf) Metal-Organic Framework

Catalysis under continuous flow operation is industrially more relevant compared to reactions carried out in batch reactors. But catalysis with metal-organic frameworks (MOFs) is largely restricted to batch reactions, especially in case of semi hydrogenation reactions. We anchored Pd nanoparticles (NPs) on robust UiO-66(Hf) MOF to develop effective catalyst for semi hydrogenation of phenylacetylene into styrene. We investigated catalytic performance of Pd/UiO-66(Hf) in a continuous-flow liquid-phase semi-hydrogenation of phenylacetylene (PA). In this study, Pd/UiO-66(Hf) catalyst exhibited good catalytic performance with a rare combination of high PA conversion (99.0 %) and high styrene selectivity (90.0 %). Additionally, Pd/UiO-66(Hf) demonstrated lower deactivation rate in contrast to many reported materials to date. The higher stability of metal NPs over UiO-66(Hf) aroused from the strong metal-support interaction (between Bronsted acidic mu(3)-OH of MOF and Pd). The Pd/UiO-66(Hf) retained its catalytic activity even after four recycles.

Automated summary

Catalysis under continuous flow operation is more relevant in industry, especially for semi hydrogenation reactions. However, catalysis with metal-organic frameworks (MOFs) is mostly restricted to batch reactions. In this study, Pd nanoparticles (NPs) were anchored on UiO-66(Hf) MOF to create an effective catalyst for semi hydrogenation of phenylacetylene into styrene. The Pd/UiO-66(Hf) catalyst showed excellent catalytic performance, with high phenylacetylene conversion (99.0%) and styrene selectivity (90.0%), and demonstrated lower deactivation rate compared to other reported materials. The strong metal-support interaction between the MOF and Pd nanoparticles contributed to the higher stability of Pd/UiO-66(Hf) catalyst.