Promoting Methyl Glycolate Yield Via Low-Temperature H2 Activation in Atmospheric Hydrogenation of Dimethyl Oxalate

The effect of reduction temperature on the low-temperature hydrogen activation capacity of Cu/SiO 2 prepared by the gel-hydrothermal method and its atmospheric pressure hydrogenation activity is investigated in this work. XPS and FTIR reveal that insufficient reduction of the catalyst occurs at low temperatures. Cu 2+ is completely reduced to lower valence species at temperature above 250 °C. XRD and N 2 O titration confirm that the Cu 0 underwent severe agglomeration at reduction temperatures above 300 °C, whereas H 2 -TPD confirms that the catalysts reduced at 250–300 °C exhibit optimal low-temperature hydrogen activation capacity. Reaction tests show that the efficient low-temperature hydrogen activation of Cu/SiO 2 catalysts is a crucial factor in improving MG yields. The catalyst reduced at 250 ~ 300 °C achieved about 90% DMO conversion and 85% MG selectivity at 170 °C and 0.1 MPa.