Effect of calcination temperature on structure and semi-hydrogenation activity of Cu/lamellar-SiO2 catalysts

A series of Cu/lamellar-SiO2 catalysts were obtained after reduction of a copper phyllosilicate precursor, which were prepared using the one-step sol–gel method followed by calcination under different temperatures varying from 400 to 700 ℃. Various characterization techniques were employed to reveal the structural properties and catalytic performance of Cu/lamellar-SiO2 catalysts. When the calcination temperature was 500 ℃, the conversion of dimethyl oxalate (DMO) was 98.5% and the selective for methyl glycolate (MG) was 52.1%. In addition, Cu/lamellar-SiO2 catalyst exhibited excellent stability during DMO hydrogenation under a pressure of 2 MPa, reaction temperature of 473 K and H2/DMO of 100. The characterization results indicated that the lamellar structure maintained in the catalyst can improve the dispersion of Cu species, and is beneficial to provide stable Cu+, thereby enhancing the selectivity of the preliminary hydrogenation product, MG.