Support effect on Cu-Ru/SiO_2 sol-gel catalysts

摘要

Cu-Ru/SiO_2, Cu/SiO_2 and Cu-Ru/SiO_2 catalysts containing 1/100 wt. of the active metal on the silica support were prepared in various ways and characterized by appropriate spectroscopic techniques. FTIR results show that the hydroxyl ions of the support is stable up at 800degC. Thermal treatment of samples does not modify BET areas, in the range of 600 m~2/g, nor the values of the average size of the metlalic particles. The study of the catalytic activity using the phenyacetylene hydrogenation test reaction shows that the Cu-Ru/SiO_2 catalysts have high activity and selectivity to styrene. However, when Cu is additionally impregnated into these solids, no activity is observed in the test reaction of hydrogenolysis of n-heptane. Finally, all catalysts show good activity in the reduction of NO_x by CO.