Active ruthenium species in acetylene hydrochlorination

A series of ruthenium-based catalysts were prepared using spherical activated carbon as a support with the treatment of oxidation or reduction. The catalytic performances of the prepared catalysts were assessed in the hydrochlorination of acetylene based on their characterisation by BET, TG, TEM, TPR, Raman, and XPS. The best catalytic performance was achieved with the oxidised catalyst Ru/SAC-C300, which exhibited a stable acetylene conversion at 96.5% in 48 h at 170 degrees C and a GHSV (C2H2) of 180 h(-1). It is proposed that there exist three major active sites on the surface of Ru-based catalysts for acetylene hydrochlorination, i.e., the oxidised site (RuO2), the reduced state (metallic Ru) and the complexes of Ru/RuOy. Compared with the active ingredient of metallic Ru and Ru/RuOy through the reductive treatment, the active ingredient of RuO2 is key for improving the catalytic performance of Ru-based catalysts through the oxidative treatment, which provides a promising route to explore high efficient non-mercuric catalysts for acetylene hydrochlorination. (C) 2014 Elsevier B.V. All rights reserved.