Abstract
Ni-modified Ag/SiO(2) catalysts containing 0~3 wt.% Ni were obtained by impregnating Ni species onto Ag/SiO(2) followed by calcination and reduction. The catalysts' performance in the hydrogenation of dimethyl oxalate (DMO) to methyl glycolate (MG) was tested. Ag-0.5%Ni/SiO(2) showed the highest catalytic activity among these catalysts and exhibited excellent catalytic stability. The effects of the Ni content on the structure and surface chemical states of catalysts were investigated by XRF, N(2)-sorption, XRD, TEM, EDX-mapping, FT-IR, H(2)-TPR, UV-vis, and XPS. The better catalytic activity and stability of Ni-modified Ag/SiO(2) (versus Ag/SiO(2)) are ascribed to the improved dispersion of active Ag species as well as the higher resistance to the growth of Ag particles due to the presence of Ni species.