Effect of Ti on Ag catalyst supported on spherical fibrous silica for partial hydrogenation of dimethyl oxalate

A highly efficient Ag catalyst supported on a novel Ti-decorated spherical fibrous silica (Ag/Ti-KCC-1) was synthesized via a facile approach. Characterization of catalysts, including FT-IR, N 2 physisorption, TEM, ICP-OES and DRUV–vis was carried out to investigate the physicochemical properties of the catalyst, XPS, H 2 -TPR, H 2 -TPD and DMO-TGA were conducted to further elucidate the effect of Ti dopant. It is shown that the Ti additive is able to, (1) inhibit the aggregation of Ag; (2) induce electron transfer from Ti to Ag, which effect the Ag dispersion and the adsorption ability of the reactants on the catalyst surface. Proper amount of Ti additive provided a balanced coverage of both hydrogen and dimethyl oxalate (DMO) on catalyst surface, which is essential in promoting the performance of the catalyst in the hydrogenation of DMO. By using the novel 10Ag/0.02Ti-KCC-1 catalyst, a high MG yield of 93.0% under extremely high WHSV of 1.75 h −1 is achieved.