Current time in Korea 01:18 Oct 20 (Fri) Year 2017 KCS KCS Publications
KCS Publications
My Journal Log In Register
HOME > Search > Browsing(BKCS) > Archives

Bulletin of the Korean Chemical Society (BKCS)

ISSN 0253-2964(Print)
ISSN 1229-5949(Online)
Volume 35, Number 6
BKCSDE 35(6)
June 20, 2014 

 
Title
A Deep Investigation of the Thermal Decomposition Process of Supported Silver Catalysts
Author
Jun Jiang, Tianhao Xu, Yaping Li, Xiaodong Lei, Hui Zhang, D. G. Evans, Xiaoming Sun*, Xue Duan
Keywords
Silver, Supported catalyst, Thermal decomposition, Activation, Epoxidation
Abstract
A deep understanding of the metallic silver catalysts formation process on oxide support and the formation mechanism is of great scientific and practical meaning for exploring better catalyst preparing procedures. Herein the thermal decomposition process of supported silver catalyst with silver oxalate as the silver precursor in the presence of ethylenediamine and ethanolamine is carefully investigated by employing a variety of characterization techniques including thermal analysis, in situ diffuse reflectance infrared Fourier transform spectroscopy, scanning electron microscopy, and X-ray diffraction. The formation mechanism of supported silver particles was revealed. Results showed that formation of metallic silver begins at about 100 oC and activation process is essentially complete below 145 oC. Formation of silver was accompanied by decomposition of oxalate group and removal of organic amines. Catalytic performance tests using the epoxidation of ethylene as a probe reaction showed that rapid activation (for 5 minutes) at a relatively low temperature (170 oC) afforded materials with optimum catalytic performance, since higher activation temperatures and/or longer activation times resulted in sintering of the silver particles.
Page
1832 - 1836
Full Text
PDF