二步法催化氧化苯甲醛合成苯甲酸工艺研究
Study on preparation technology of benzoic acid by catalytic oxidation of beznaldehyde with two-step method
关昶 1刘亚歌 2丁斌 1郝凤岭 1李祥1
作者信息
- 1. 吉林化工学院,化工与材料工程学院,吉林吉林132022
- 2. 中国石油东北炼化工程有限公司,吉林设计院,吉林吉林132012
- 折叠
摘要
采用2步法催化氧化苯甲醛合成苯甲酸，氧化剂为过氧化氢，催化剂为钨酸钠．其中过氧化氢分两次加入，第1次加入总量40％的过氧化氢，第2次加入剩余的过氧化氢．实验结果表明，2步法加入过氧化氢得到的苯甲酸收率为56．22％，明显高于1步法的苯甲酸的收率．对首次加入过氧化氢时的物料比进行了正交试验，最佳合成条件为n（H2O2）／n（Na2WO4．2H2O）：n（NaHSO4）：n（C6H5CHO）：100：1．2：1：250．同时考察了2步法反应的回流时间对收率的影响，结果表明第1步的反应时间3h，第2步反应的时间5h的反应条件最优．
Abstract
Benzoic acid was prepared by catalytic oxidation of benzladyde with two-step method, the H2O2 was used as oxidant and the Na2WO4.2H2O was used as catalyst. The H2O2 was added twice in this method,and in the first step there was 40% of H2O2. The results show that the two-step feed way can observably improve the yield of benzoic acid,which can reach 56.22%. The effect of the first-step feed way on the oxidation reaction was discussed. The yield can reach 67.79% at the condition of molar ration of n （ H2O2 ）/n （ Na2WO4.2 H2 O） / n（ NaHSO4 ）/n（ C6H5CHO） = 100 ： 1.2 ： 1 ： 250. The effect of the return time on the yield coefficient was also discussed. The results show that the preferable retune time was 3 h in the first step and 5 h in the second step.
关键词
催化氧化/苯甲酸/过氧化氢/正交试验/加料方式Key words
catalytic oxidation/benzoic acid/hydrogen peroxide/orthogonal test/adding method引用本文复制引用
出版年
2012
NETL
NSTL
维普
万方数据