Journal of Catalysis p. 195 - 205 (1994)
Update date:2022-08-10
Topics:
Khouw, C. B.
Dartt, C. B.
Labinger, J. A.
Davis, M. E.
Titanium containing, aluminum-free ZSM-5 (TS-1) and amorphous TiO2-SiO2 coprecipitate are investigated as catalysts for the selective oxidation of alkanes and alkenes using a variety of oxidants at temperatures below 100 deg C. Comparisons between the activities of TS-1 and the TiO2-SiO2 coprecipitate for alkane oxidation and alkene epoxidation using nonaqueous H2O2 indicate that the absence of water is crucial for the catalytic activity of silica-supported titanium. Due to the hydrophobicity of TS-1, the concentration of water surrounding the titanium is maintained at a low value, and thus TS-1 can be used as an oxidation catalyst with aqueous H2O2 as oxidant. Alkyl hydroperoxides are active as oxidants for alkene epoxidation on the TiO2-SiO2 coprecipitate but not for alkane oxidation reactions on both TS-1 and the TiO2-SiO2 coprecipitate. A plausible explanation for the above results is provided. The presence of stereoscrambling without any "radical clock" rearrangement during alkane oxidation on TS-1 indicates that the radicals formed may have a very short life-time, or their movements are restricted such that no rearrangement can occur. A proposal for the mechanism of alkane oxidation on TS-1 is given and compared to a mechanism suggested for alkene epoxidation on TS-1 and the TiO2-SiO2 coprecipitate.
View MoreJiangxi Lixin Pharmaceutical Co.,Ltd.
Contact:0798-8337222; 18979813215
Address:Jiangxi City, Jindezheng Province
AstaTech ( Chengdu) BioPharmaceutical Corp.
website:http://www.astabiochem.cn/
Contact:+86-15680585308
Address:SICHUAN CHENGDU
Nanjing Vincero International Trading Co.,Ltd
Contact:8618936897229
Address:NO.68, ZhuShan Road, JiangNing WanDa Plaza, Building E Room 1703
Qingdao Kingway Pharmtech Co., Ltd.
Contact:86-532-87118899
Address:No. 88, Middle Haixi Road, Jiaonan City, Qingdao, China
SHANDONG QINGYUNCHANGXIN CHEMICAL SCIENCE-TECH CO.,LTD
Contact:86-21-60560171
Address:1689Donghuan Rade,Qingyun County, Dezhou City, Shandong,China
Doi:10.1021/om00064a001
(1982)Doi:10.1021/acs.jmedchem.7b01066
(2017)Doi:10.1021/jo00001a047
(1991)Doi:10.1021/jo00939a025
(1974)Doi:10.1107/S0108270101006965
(2001)Doi:10.1039/j39680002751
(1968)