Construction of Ru–N Single Sites for Effective Acetylene Hydrochlorination: Effect of Polyethyleneimine Modifiers

Several single-site catalysts have been synthesized through the chelation of polyethyleneimine (PEI) with Ru precursors because of the lack of durable active sites in Ru catalysts for acetylene hydrochlorination. Proper thermal activation successfully constructed the local active domains of Ru–N. Ru species were stabilized in their active states by coordinating N in PEI with the central atom Ru in the Ru/activated carbon (AC) catalyst. The metal and highly electronegative heteroatomic sites in the Ru–N domains augmented the activation ability of reactant molecules synergistically. The synthetic strategy developed led to the dispersion of active metal at the level of a single site. Additionally, more Ru–N–C interfaces formed after appropriate pyrolysis of the catalyst (Ru/AC@PEI-T), increasing the contact area to reactants and improving the catalytic efficiency. The modified Ru/AC@PEI catalyst has significantly enhanced catalytic stability over time, allowing for possible industrial applications.