草酸二甲酯气相催化加氢合成乙二醇的研究

采用共沉淀法制备了一系列 CuO/SiO₂ 催化剂,进行草酸二甲酯气相加氢活性评价,分别考察了不同沉淀剂（Na₂CO₃、NH₃·H₂O、NaOH）、催化剂组成以及反应工艺条件对加氢性能的影响。采用N₂ 吸附脱附、N₂O吸附、XRD、TG热重分析、H₂-TPR等手段对催化剂进行表征。结果表明，草酸二甲酯加氢反应活性与Cu⁰有关,提高铜比表面积有利于提高加氢活性。采用以NaOH沉淀剂制备的CuO质量分数为50%的CuO/SiO₂催化剂,在200℃、2MPa、0.07h^-1和氢酯摩尔比为100时,草酸二甲酯转化率可达 98%,乙二醇选择性87%,且催化剂表现出较好的稳定性。

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.