Zr(OH)4‐Catalyzed Semi‐Hydrogenation of Phenylacetylene with Terminal Zr‐O‐H as Active Site: Inactive for Free Styrene

In the field of industrial semi‐hydrogenation of trace alkynes amidst alkene feedstocks, the pivotal challenge lies in circumventing the hydrogenation of alkenes. Herein, we present Zr(OH) 4 as an innovative catalyst for the semi‐hydrogenation of phenylacetylene, demonstrating remarkable selectivity towards styrene (>96 %), while exhibiting inactivity towards free styrene. Notably, Zr(OH) 4 achieves a 95 % conversion of quasi‐industry 1 mol % phenylacetylene within styrene, with a mere 0.44 % styrene loss. Experimental and theoretical results confirm both terminal Zr−O−H and bridge Zr−O−H can dissociate H 2 , while the terminal Zr−O−H plays a crucial role on activating phenylacetylene through the sequential hydrogenation process of C 6 H 5 C≡CH→C 6 H 5 C=CH 2 →C 6 H 5 CH=CH 2 . The high rate of phenylacetylene removal is attributed to its strong adsorption capacity, while Zr(OH) 4 has a significantly weaker adsorption capacity for styrene.