草酸二甲酯加氢合成乙二醇Cu/SiO_2催化剂的稳定性试验研究

Stability tests of Cu/SiO_2 catalyst for dimethyl oxalate hydrogenation to ethylene glycol

合成气经草酸二甲酯加氢制乙二醇技术在工业应用过程中存在一些技术难题,其中草酸二甲酯加氢制乙二醇催化剂的稳定性是制约该技术发展的瓶颈。以Cu/SiO_2草酸二甲酯加氢催化剂A为研究对象,通过2 600 h的稳定性实验研究,考察反应温度对草酸二甲酯转化率、乙二醇选择性以及产物中乙醇酸甲酯含量的影响,为合成气经草酸二甲酯制乙二醇技术的工业应用优化提供重要的技术支持。结果表明,当反应压力2.8 MPa、空速(0.3~0.5)h-1、氢酯物质的量比120~140和反应温度216℃时,草酸二甲酯转化率近100%,乙二醇选择性大于95.0%,产物中乙醇酸甲酯质量分数小于0.5%,Cu/SiO_2催化剂A稳定性较好。

There still existed some technical problems in engineering scale - up of ethylene glycol from syngas via hydrogenation of dimethyl oxalate. Especially the stability of the catalysts for hydrogenation of dimethyl oxalate to dimethyl has been the bottleneck limiting the further development of the technique.Cu/SiO_2 catalyst A for hydrogenation of dimethyl oxalate was selected in the experiments. The effect of reaction temperatures on the selectivity to ethylene glycol, dimethyl oxalate conversion and methyl glyco- late contents were investigated by the stability tests of Cu/SiO_2 catalyst A for 2 600 h, which had an important guiding significance for engineering scale - up of ethylene glycol production via dimethyl oxalate. The results showed that Cu/SiO_2 catalyst A exhibited good activity and stability, the selectivity to ethylene glycol of over 95.0%, dimethyl oxalate conversion of almost 100% and methyl glycolate mass fraction of less than 0.5% were attained under the condition as follows：reaction pressure 2.8 MPa,space velocity （0.3 -0.5） h-1 ,molar ratio of H_2 to dimethyl oxalate 120 -140 and reaction temperature 216 ℃.