溴酸钠催化氧化乙二醛制备乙醛酸研究

Study on the Preparation of Glyoxylic Acid by Sodium Bromate Catalyzed Oxidation Glyoxal

采用氧气和硝酸为氧化剂,溴酸钠作催化剂,在盐酸水溶液中氧化乙二醛制备乙醛酸,以减少乙醛酸生产过程中氧化氮尾气。向845 g含有乙二醛29.6%和盐酸4.25%的水溶液中,加入溴酸钠10 g,以1.5 g/h速度加入50%硝酸,连续通入氧气,在反应温度45℃,压力0.01 MPa下进行氧化反应24 h,得到含乙二醛1.31%和乙醛酸25.9%的反应完成液951 g,乙二醛转化率95.0%,乙醛酸选择性81.4%。

The glyoxal was oxidized to glyoxylic acid in hydrochloric acid solution by oxygen and nitric acid with sodium bromate as catalyst to decrease nitrogen oxide in the process.The 10 g sodium bromate was added into 845 g of solution containing 29.6% of glyoxal and 4.25% of hydrochloric acid.The dilute nitric acid of 50% was added at a rate of 1.5 g/h and oxygen was blowen continuously to the solution.Oxygen was blowen at 45 ℃ and 0.01 MPa for 24 hours to obtain 951 g reaction solution containing 1.31% of glyoxal and 25.9% of glyoxylic acid.The conversion of glyoxal was 95.0% and the selectivity to glyoxylic acid was 81.4%.