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DOI: 10.1055/s-0029-1217234
Photooxidation of Alkanes Using W10O32 4- on Organomodified SBA-15
Contributor(s):Yasuhiro Uozumi, Yoichi M. A. Yamada, Maki MinakawaEast China Normal University and Fudan University, Shanghai, P. R. of China
Photooxygenation of Hydrocarbons over Efficient and Reusable Decatungstate Heterogenized on Hydrophobically-Modified Mesoporous Silica
Chem. Commun. 2009, 2171-2173
Publication History
Publication Date:
22 June 2009 (online)
Key words
photooxidation - decatungstate - SBA-15 - mesoporous silica - heterogeneous catalysis
Significance
Photooxidation of alkanes using decatungstate W10O32 4- on a novel hydrophobically-organomodified SBA-15 as catalyst was described. The catalyst W10/C8-AP-SBA (W10=[W10O32 4-], C8 = octyl group, AP = 3-aminopropyl group) was prepared by treatment of C8H13Si(OEt)3 with SBA-15, grafting with 3-aminopropyl amine, acidification with CF3SO3H and ion exchange by decatungstate. W10/C8-AP-SBA showed photocatalytic oxidation activity for various alkanes under mild conditions to afford the corresponding ketones (7 examples, 28-97% conversion).
Comment
Elemental analysis using ICP showed that W10/Cn-AP-SBA gave ca. 12wt% loading of decatungstate. After the first oxidation of ethylbenzene, the catalyst was separated from the reaction mixture by filtration. The recovered catalyst was reused five times without any loss of catalytic activity. TEM and IR analysis showed no change in the nanostructure of the SBA-15 support and decatungstate species of the fifth reused catalyst, respectively. It was confirmed by ICP analysis that the W content in the used W10/C8-AP-SBA catalyst was the same as that in the fresh catalyst and that no W was detected in the filtrate.