摘要
用共沉淀和浸渍法分别制得镁铝水滑石固载MnO4-催化剂HT-MnO4-,并将该催化剂在温和条件下、以分子氧为氧化剂用于催化醇的液相氧化反应。以苯甲醇氧化反应为模型探讨了不同制备方法制得的催化剂以及温度、溶剂等条件对反应的影响,结果显示两种制备方法对催化性能影响的差别不大,非极性溶剂更有利于反应进行,苯甲醇转化率随着温度上升明显提高。XRD表征给出水滑石经过MnO4-阴离子交换以后,X射线衍射峰中最强峰对应晶面的平均粒径减小,但结构仍然完整;XPS表征表明HT-MnO4-中Mn的结合能较之KMnO4中的Mn有所降低。说明镁铝水滑石负载高锰酸钾远比高锰酸钾温和,在醇的液相氧化中同时起着催化剂和氧化剂的作用。
Mg-Al hydrotalcite-supported MnO4^- catalysts （HT-MnO4^-） were prepared separately by two different preparation methods （coprecipitation and impregnation methods）, and their application to liquid-phase oxidation of alcohols in the present of molecular oxygen under mild condition was studied by using the oxidation of benzyl alcohol as the model alcohol oxidation reaction. It was found that the two HT-MnO4^- preparation methods exhibit only a few catalytic performance differences during alcohol oxidation reaction, while elevating reaction temperature and using non-polar solvent will favor the alcohol oxidation reaction. The XRD characterization of HT-MnO4^-shows that, since the anion MnO4^- substitutes the anion CO3^2- in the middle layer of hydrotalcite （HT）, the average particle size of the crystal face corresponding to the most intensive X-ray diffraction peak decreases, while the structure of the HT remains unchanged. The XPS characterization indicates that the binding energy of Mn in HT-MnO4^- decreases in comparison with that in KMnO4. The oxidative performance of HT-MnO4^- is milder than that of KMnO4, and the Mg-Al hydrotalcite -supported MnO4^- catalyst plays dual roles of the catalyst and the oxidant in the alcohol oxidation reaction.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2008年第4期604-610,共7页
Journal of Chemical Engineering of Chinese Universities
基金
国家自然科学基金(20576045)
新世纪优秀人才支持计划(NCET-06-740)资助
关键词
镁铝水滑石
高锰酸根阴离子
表征
醇氧化
Mg-Al hydrotalcite
MnO4^- anion
characterization
alcohol oxidation
