Study on performance of Ag-modified layered copper silicate catalyst for hydrogenation of dimethyl oxalate to methyl glycolate

Methyl glycolate (MG) is a high value-added chemical intermediate and widely used in the fields of medicine, chemical industry, fodder and dyes. A series of CuAg/SiO₂ catalysts were prepared by sol-gel method for hydrogenation of dimethyl oxalate to MG. The structure of catalysts was characterized by XRD, N₂-physical adsorption, FT-IR, TEM, H₂-TPR, and XPS, and the influence of Ag loading on catalytic performance was investigated. The 5Ag-Cu/SiO₂ catalyst with Ag loading of 5% exhibited the best catalytic performance with DMO conversion of 83.7% and MG selectivity of 72.2%. The characterization results showed that introducing appropriate amount of Ag not only improved the dispersion of copper species, but also increased the content of Cu⁺, thereby improving the catalytic activity of CuAg/SiO₂ catalysts. In addition, the electron transfer between Ag and Cu could effectively stabilize Cu⁺, and eventually improved the stability of the catalyst.