季铵盐相转移催化氧化合成苯甲酸  

Phase Transfer Catalysis Oxidation to Synthesize Benzoic Acid with Quaternary Ammonium Salt

作　　者：刘明[1] 傅杰[1] 沈昱[1] 曹魁[1] LIU Ming FU Jie SHEN Yu CAO Kui(School of Environmental and Chemical Engineering, Dalian Jiaotong University, Dalian 116028, China)

机构地区：[1]大连交通大学环境与化学工程学院,辽宁大连116028

出　　处：《大连交通大学学报》2017年第5期85-88,共4页Journal of Dalian Jiaotong University

摘　　要：应用相转移催化技术,研究十六烷基三甲基溴化铵(CTMAB)在水溶液中以高锰酸钾为氧化剂,氧化甲苯制备苯甲酸的催化性能,并与该实验未采用催化剂的课堂教学进行对比.结果表明,在甲苯小量化操作条件下,当n(CTMAB)∶n(甲苯)=1∶20,反应时间缩短至1.5 h,KMn O4用量下降至n(KMn O4)∶n(甲苯)=2.13∶1,但收率增加至47.8%.试剂用量减少、反应时间缩短,但产率却有效增加可归因于:CTMAB改变反应体系由"甲苯-水"二相体系为均相体系;固体KMn O4分批投料不仅抑制KMn O4自身分解,并且粘附在回流柱底端的高锰酸钾与甲苯回流液能在此处发生二次反应.该实验操作简单、安全省时、绿色环保.The catalytic activity was evaluated by using cetyl trimethyl ammonium bromide （CTMAB） as phase transfer catalyst to synthesize benzoic acid with KMnO4 oxidation treatment. The yield of benzoic acid was compared with that of teaching practice in the synthesis of benzoic acid without CTMAB. These results suggest that the yield of benzoic acid could reach 47.8% under the conditions of toluene 1.4 mL and the mo- lar ratios was 1 ： 20 and 2.13 ： 1 of CTMAB and KMnO4 versus toluene at 95~C for 1.5 h. The reduction of the regent consumption, the shortening of reaction time and the increase of the yield are mainly contributed by homogeneous reaction system by CTMAB addition, catastaltic self - decomposition rate by the way of batch addition of solid KMuO4 , the secondary reaction between toluene and KMnQ powder located at the bottom of reflux column. This experiment is easy to operate and environmental friendly.

关 键 词：相转移催化 十六烷基三甲基溴化铵 小量化反应 苯甲酸 氧化 

分 类 号：TQ245.12[化学工程—有机化工]