煤制乙二醇中间产物草酸二甲酯水解制草酸工艺研究

Study on the hydrolysis of dimethyl oxalate——MEG intermediate to oxalic acid

主要模拟生产流程对草酸二甲酯水解制备草酸进行研究,试验从5个关键因素着手,其中水解反应时间、水解温度、水酯比对水解转化率影响较大,增长反应时间、提高反应温度和增大水酯比均有利于提高草酸二甲酯转化率;搅拌速率对草酸二甲酯水解转化率影响不大,只要能满足传热要求即可;烘干过程即保证游离水蒸发,也尽可能避免草酸升华损失,选取105~120℃烘干3.5~4 h。

In this paper,the hydrolysis of dimethyl oxalate to oxalic acid was studied by simulating the production process,and The experiment started with five key factors.It was found that the hydrolysis reaction time,hydrolysis temperature and water-ester ratio had great influence on the hydrolysis conversion.Increasing the reaction time,increasing the reaction temperature and increasing the water-ester ratio were conducive to improving the conversion of dimethyl oxalate;The stirring rate has little influence on the hydrolysis conversion of dimethyl oxalate as long as it can meet the heat transfer requirements;The drying process not only ensures the evaporation of free water,but also avoids the loss of oxalic acid sublimation as far as possible.Drying at 105~120℃for 3.5~4 hours is selected.