苯甲醛是一种重要的化学中间体和美国食品药物管理局认证的添加剂.现代化工生产苯甲醛的工艺存在很多的不足,本文通过向溶剂中添加乙酸酐的方法提高了苯甲醛的选择性和产率,讨论了乙酸酐在甲苯氧化过程中的作用,并获得其优化工艺条件.在该条件下苯甲醛选择性最高达68.69%,产率最高为26.12%,且反应温度(98℃),反应压力(1 atm O2)都较之前报道的文献温和很多,该反应条件有腐蚀性低、能耗低、副产物少等优点.此外,本文还研发出一种简便有效的催化剂回收方法.
Benzaldehyde is an important chemical intermediate and F.D.A.-approved synthetic flavoring substance.There are many drawbacks in the present industrial processes and the improvements are urgently required.In this study,we increased the selectivity and yield of benzaldehyde by simply adding acetic anhydride(AA).The role of AA was investigated and an easier recycling procedure for catalysts was developed.At a mild reaction temperature of 9 8 ℃ and rather low pressure of 1 atm oxygen,which gives the advantages of lower equipment corrosion rate,the lower energy cost,and less by-products,the selectivity and yield of benzaldehyde can reach as high as 68.69% and 26.12%,respectively.