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3 h,第2步反应的时间5 h的反应条件最优.
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.
出处
《吉林化工学院学报》
CAS
2012年第1期19-21,共3页
Journal of Jilin Institute of Chemical Technology
关键词
催化氧化
苯甲酸
过氧化氢
正交试验
加料方式
catalytic oxidation
benzoic acid
hydrogen peroxide
orthogonal test
adding method
