Enhanced catalytic performance of activated carbon-supported ru-based catalysts for acetylene hydrochlorination by azole ligands.

• The catalysts were prepared by coordinating the Ru precursor with azole ligands. • The Ru-L 8 /AC catalyst exhibited the superior performance to the other catalysts. • The coordination helps to stabilise high valence Ru and produce more active species. • The coordination contributes to the anchoring and dispersion of active species. • The interaction enhanced the adsorption ability for reactants. Supported Ru-L x /AC catalysts were synthesised by coordinating a Ru precursor with several azole ligands and assessed for acetylene hydrochlorination. The results demonstrated that the coordinated Ru-imidazole/AC (Ru-L 1 /AC) catalyst exhibited superior catalytic activity compared to that of catalysts coordinated with other ligands. In addition, the substitution of hydrogen on the imidazole ring by electron-donating substituents further improved the catalytic performance. Specifically, the coordination between the ruthenium precursor and heteroatom in the ligands, which contain a conjugated structure and an electron-donating substituent, promoted the transfer of electrons from the heteroatom to Ru cation and augmented the electron cloud density around the active centres, which helps stabilise high-valence Ru and produce more active Run+ species. In addition, the coordination contributed to the anchoring and dispersion of active species, which improved the catalytic hydrochlorination of acetylene. Thus, the as-designed Ru-1-isopropyl imidazole/AC (Ru-L 8 /AC) catalyst exhibits a superior performance and good application prospect. [ABSTRACT FROM AUTHOR]