对氯苯甲醛氧化合成对氯苯甲酸的研究

Study on Oxidation Synthesis of p-Chlorobenzoic Acid with p-Chlorobenzaldehyde and Potassium Bromate

在醋酸溶液中,以对氯苯甲醛、溴酸钾为原料合成对氯苯甲酸,考察了反应温度、反应时间、原料物质的量比、溶剂用量对合成反应的影响,确定了最佳工艺条件:反应温度为90～95℃,反应时间为120 min,n(对氯苯甲醛)∶n(溴酸钾)=1∶0.40,溶剂用量为35 mL(对氯苯甲醛为0.1 mol)。在最佳工艺条件下,对氯苯甲酸产品收率可达96.86%,纯度可达98.5%以上。

p -Chlorobenzoic acid was synthesized with p -chlorobenzaldehyde and potassium bromate in acetate solution as the materials, and the effect of reaction temperature, reaction time, molecular ratio of materials and solvent usage on the synthesis reaction was studied. The optimum process conditions were identified as follows： reaction temperature： 90 to 95℃, reaction time： 120 min, n（p -chlorobenzaldehyde） ： n（potassium bromate） = 1：0.40, solvent usage： 35 mL （for 0.1 mol p -chlorobenzaldehyde）. The yield ofp - chlorobenzoic acid can be as high as 96.86% and the purity ofp - chlorobenzoic acid product can be 98： 5% or more at such conditions.