MnK/Al_2O_3催化苯甲醇液相氧化制苯甲醛  

Preparation of Benzaldehyde by Oxidating Benzyl Alcohol with Mn K/Al_2O_3 Catalyst in Liquid-Phase

作　　者：汤清虎[1] 王京[1] 黄晓娜[1] 赵卉茹[1] 魏志伟[1] 赵培正[1] 

机构地区：[1]河南师范大学化学化工学院,绿色化学介质与反应省部共建教育部重点实验室,河南新乡453007

出　　处：《高校化学工程学报》2014年第6期1360-1365,共6页Journal of Chemical Engineering of Chinese Universities

基　　金：河南省高校科技创新人才支持计划项目(2010HASTIT028);河南省教育厅科学技术研究重点项目(14A150043)

摘　　要：采用共浸渍法制备Mn1K1/Al2O3催化剂,并以分子氧为氧化剂考察了其在苯甲醇液相氧化制苯甲醛反应中的催化性能。实验结果显示,焙烧温度和负载量对催化剂性能有重要影响,773 K焙烧的10%(wt)Mn1K1/Al2O3具有最高的催化活性,373 K下反应3 h时,苯甲醇转化率为72.9%,苯甲醛选择性为99%,且该催化剂可循环使用6次以上而其催化活性无明显降低。粉末X射线衍射(XRD)、N2物理吸附、拉曼光谱、X射线吸收光谱(XAS)、程序升温还原(H2-TPR)结果表明,负载在Al2O3表面的非晶态或小晶粒α-Mn O2是催化活化分子氧发生醇氧化反应的高活性物种。Mn1K1/Al2O3 was synthesized by the co-impregnation method, and was employed as the catalyst for the selective oxidation of benzyl alcohol to benzaldehyde in liquid-phase using molecular oxygen as the oxidant. The experimental results showed that calcination temperature and Mn-loadings of Mn1K1/Al2O3 could play an important role on its catalytic properties. The catalytic activity of 10%（wt） Mn1K1/Al2O3 calcined at 773 K was the highest. Up to 72.9% of benzyl alcohol conversion with 99% of benzaldehyde selectivity was achieved at 373 K in 3 h. The catalyst could be recycled up to six runs without appreciable loss of its activity. The characterizations of powder X-ray diffraction （XRD）, N2 physisorption, Raman spectroscopy, X-ray absorption spectroscopy （XAS）, and hydrogen temperature-programmed reduction （H2-TPR） suggested that the amorphous manganese oxides or small crystalline α-MnO2 particles supported on Al2O3 were the high active species for benzyl alcohol oxidation with molecular oxygen.

关 键 词：二氧化锰 钾 苯甲醇 苯甲醛 分子氧 液相氧化 MNO2 

分 类 号：TQ426.8[化学工程]