苯甲醛氧化制备苯甲酸的研究

Study on Preparation of Benzoic Acid by Catalytic Oxidation of Benzaldehyde

摘要: 以氧气为氧化剂,在六水合氯化钴催化剂作用下,催化氧化苯甲醛制备苯甲酸,分别考察了温度、溶剂量、催化剂量、乳化剂量对苯甲酸收率的影响.在苯甲醛:水:乳化剂:六水合氯化钴质量比为75:50:37.5:0.075,反应温度75～80℃,反应时间6 h,氯气流量0.3 L/min下反应,产率在85%以上,用水进行两次重结晶,得率为60%～65%.

Abstract: Benzoic acid was prepared by catalytic oxidation of benzaldyde with oxygen in the presence of cobalt chloride hexahydrate. The effects of the reaction temperature, dosage of solvent, catalyst and emulsifier on the yield of benzoic acid were studied. The yield was over 85% at the condition of mass ratio of benzaldehyde, water, emulsifier, and cobalt hexahydrate 75:50:37.5:0.075,reaction temperature 75-80℃, reaction time 6h, oxygen flow rate 0.3 L/min. The yield of benzoic acid was 60%-65% after twice recrystallization with water.