期刊
MOLECULAR CATALYSIS
卷 460, 期 -, 页码 16-26出版社
ELSEVIER SCIENCE BV
DOI: 10.1016/j.mcat.2018.09.007
关键词
Amorphous copper-chromium oxides; Tetrahedrally coordinated Cu ions; Selective oxidation of cyclohexane
资金
- National Natural Science Foundation of China [21703101]
- Program to Cultivate Outstanding Young Key Teachers of Nanjing Normal University (Qinglan Project)
- Priority Academic Program Development of Jiangsu Higher Education Institutions
In this work, amorphous copper-chromium catalysts with different Cu/Cr molar ratios have been prepared by a sol-gel method and were used in the oxidation of cyclohexane to KA-oil. The catalysts have been characterized by a variety of analytical techniques including XRD, XPS, Raman, FT-IR, BET, TEM and SEM. XRD results confirmed that the formation of amorphous structure. The XPS and Raman results indicated that most of Cu species existed in well-dispersed tetrahedral coordination before calcination. After calcination, the tetrahedrally coordinated Cu ions are transformed into octahedral coordination and the activity of catalyst is significantly reduced. The results show that the tetrahedrally coordinated Cu ions play the synergistic catalytic role with Cr ions. Interestingly, oxidation of cyclohexane is more inclined to produce cyclohexanol with uncalcined catalyst due to the presence of the tetrahedrally coordinated Cu ions; however, the appearance of surface lattice oxygen makes the reaction more conducive to cyclohexanone after calcination. After optimizing conditions, Cu-Cr oxide catalyst with the molar ratio 1:1 shows the highest activity, which obtains 62.2% yield and 92.4% selectivity for KA-oil using H2O2 as oxygen source.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据