硅钨酸催化下甲苯的选择性硝化  

Selective Nitration of Toluene at the Presence of Silicotungstic Acid Catalyst

作　　者：刘丽荣[1] 吕春绪[1] 张晓波[2] 

机构地区：[1]南京理工大学化工学院,江苏南京210094 [2]淮海工学院化学工程系,江苏连云港222005

出　　处：《含能材料》2008年第3期341-343,共3页Chinese Journal of Energetic Materials

基　　金：江苏省自然科学基金(BK99071)资助项目

摘　　要：研究了硅钨酸对甲苯硝化反应的催化活性。通过气相色谱研究了诸如催化剂用量、催化剂焙烧温度、硝化反应时间、硝化反应温度及催化剂的重复使用等因素对甲苯硝酸硝化区域选择性的影响。结果表明,在醋酐存在条件下,以CCl4为溶剂,以质量分数为95%的硝酸为硝化剂,反应温度控制在50℃,反应60 min,1.0 g经300℃焙烧1.5 h后的硅钨酸催化剂,对甲苯表现出强的区域选择性,甲苯硝化产物o/p值(甲苯硝化产物邻位和对位异构体的质量比)达0.89,较硝硫混酸的1.67显著降低,产物收率达到91.6%。该催化剂可循环使用5次,催化活性变化很小。Catalytic activity of silicotungstic acid for nitration of toluene was studied. Effects of some factors, including dosage of catalyst, calcination temperature of catalyst, nitrated reaction time and recovered catalyst, on the selectivity of toluene in mononitration at the presence of silicotungstic acid catalyst were studied hy gas chromatography （ GC ）. The results show high selectivity when the temperature is controlled at 50 ℃, and the nitrated reaction time is 90 min, toluene is nitrated by using 95% nitric acid as nitrating reagent at the presence of acetic anhydride, 1.0 g silicotungstic acid catalyst is calcinated at 300 ℃ for 1.5 h. The o/p （ ratio of ortho to paro isomer of toluene nitration） ratio is 0.89 in product distribution of toluene nitration, lower than 1.67 using sulfonitric acid as catalyst. The yield of products is 91.6%. The catalyst can be reutilized up to five times with little decrease in activity.

关 键 词：应用化学 硅钨酸 催化剂 甲苯 选择性硝化 

分 类 号：O643.32[理学—物理化学]