H_2对CO偶联制备草酸二甲酯反应影响的研究

Effect of H_2 on coupling of CO with methyl nitrite to dimethyl oxalate

考察了H2对CO偶联反应合成草酸二甲酯(DMO)反应的影响。发现催化剂钯表面的吸附先后顺序为H2、亚硝酸甲酯、CO。随着H2浓度的升高,甲酸甲酯会大量生成,甲醇也会生成,偶联反应产物DMO和副产物碳酸二甲酯的生成明显减少,并初步探讨了H2对偶联反应造成影响的原因。确定了一个H2对反应产生影响的最小值,抑制H2影响的有效手段是加大反应气体的线速度。

Effect of H2 impurity in feed gas on the coupling of CO with methyl nitrite （MN） to dimethyl oxalate （DMO） was studied. It was found that the adsorption order was H2≥MN〉DMO on Pd surface of the catalyst. When H2 in the reaction system increased to above a certain value, a large amount of methyl formate and some methanol would be formed, and DMO yield and dimethyl carbonate formation decreased obviously. The mechanism of H2 affecting the reaction was discussed. The lowest H2 concentration affecting the reactions was determined. Increasing the linear velocity of the reactants was an effective way to inhabit H2 impact.