Study on hydrogenation of dimethyl oxalate to ethylene glycol

Vapor-phase hydrogenolysis of dimethyl oxalate to ethylene glycol was performed over a series of CuO/SiO₂ catalysts with different precipitants(Na₂CO₃，NH₃·H₂O，NaOH) and CuO loading in a fixed-bed reactor at different reaction conditions. All catalysts were characterized by N₂ physisorption, N₂O-chemisorption, X-ray diffraction (XRD), TG and H₂ temperature- programmed reduction (H₂-TPR) analysis technique. The results of catalytic tests and characterization indicate that the activity of catalysts is related with the Cu⁰ and improved with the increase of the Cu area. High conversion of dimethyl oxalate(98%) and selectivity to ethylene glycol(87%) were obtained over the optimal CuO/SiO₂ catalyst (precipitated by NaOH and 50% CuO loading) at optimized reaction conditions. The CuO/SiO₂ catalyst also exhibits good stability.