一步法催化氧化环己烯制备己二酸的工艺研究

Study on the process of preparating adipic acid by catalytic oxidation cyclohexene with “one-pot” method

摘要:

用“一锅煮”的方法将自制的催化剂400PW/SBA(40)（简记为PW/SBA）用于过氧化氢氧化环己烯制备己二酸的绿色工艺中,该工艺无溶剂化。通过己二酸合成预试验，确定了环己烯和过氧化氢的摩尔比为5.47:1，用正交试验法和单因素实验法优化反应工艺条件，考察了反应时间、催化剂用量、反应温度和加料方式对己二酸收率、纯度的影响。确定出较优工艺条件为：反应时间9h，温度80℃，催化剂用量1.75g，n(H2O2): n(环己烯)=5.47:1(环己烯以5.3ml，0.0497mol 计)，反应3.5h后加入另外1/2量的w(H2O2)=30%。通过3次平行实验，己二酸产品的收率可达74.5%，纯度可达99.7%。并对PW/SBA进行表征，得出其氮气吸附等温线和BJH孔容曲线。

Abstract:

Adipic acid is synthesized by means of a “one-pot” reactive mode with cyclohexene and hydrogen peroxide(w=30%) using modified catalyst 400PW/SBA(40)（brief note PW/SBA）. The process is the scientific method of clean synthesis becauce of no organic solvents. Three steps were taken in the study to optimize the conditions of the synthesis process of adipic acid. First of all, the basic route of synthesizing adipic acid was determined by pre-experiment program. Then the orthogonal experiments method and the single factor test method was used to optimize the conditions of reaction process. Finally, the better process of synthetic routes and conditions was tested by using the parallel experiment methods . The obtained condition is reaction time 12h, temperature 80℃, the amount of catalyst 1.75g, n(H2O2): n(cyclohexene)=5.47:1, adding the amount of another 1/2H2O2 after reaction time is 3.5h. The results indicate that the yield of adipic acid could reach 74.5% , and purity quotient 99.7% under the optima condition. Moreover, characterized N2 adsorption–desorption isotherms and BJH cumulative pore volume of the PW/SBA were investigated.