煤制乙二醇工艺中草酸二甲酯合成控制要点

Key Points and Control of Synthesis of Dimethyl Oxalate in Coal-to-ethylene Glycol Route

简要介绍了CO羰化偶联生产草酸二甲酯的反应机理,并系统性的阐述了反应温度、各组分浓度变化及杂质气体含量对草酸二甲酯收率的影响。结果表明:将温度和CO/亚硝酸甲酯的物质的量的比分别控制到110~140℃、0.8~1.5的范围内,则更有利于草酸二甲酯的生成。此外,H_(2)相较于CO和MN而言,其在钯式催化剂表面的吸附能力更强,其浓度应控制在500 ppm以下。而原料气中氨含量的增加,会导致催化剂的反应活性较低,因此原料气中杂质含量越低越有利于草酸二甲酯的合成。

The reaction mechanism of CO carbonylation coupling to produce dimethyl oxalate was briefly introduced,the effects of reaction temperature,changes in component concentrations,and impurity gas content on the yield of dimethyl oxalate were systematically elaborated.The results indicated that controlling the temperature and the ratio of CO/methyl nitrite to the amount of material within the range of 110 to 140 ℃ and 0.8 to 1.5 respectively was more conducive to the generation of dimethyl oxalate.In addition,compared to CO and MN,H_(2) has stronger adsorption capacity on the surface of palladium catalysts,and its concentration should be controlled below 500 ppm.The increase in ammonia content in the feed gas will lead to a lower reaction activity of the catalyst,so the lower the impurity content in the feed gas,the more conducive it is to the synthesis of dimethyl oxalate.