Preparation and Characterization of Cs2.8H1.2PMo11Fe(H2O)O39·6H2O and Investigation of Effects of Iron-Substitution on Heterogene
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- 作者：Noritaka Mizuno ; Joon-Seok Min ; and Akira Taguchi
- 刊名：Chemistry of Materials
- 出版年：2004
- 出版时间：July 13, 2004
- 年：2004
- 卷：16
- 期：14
- 页码：2819 - 2825
- 全文大小：107K
- 年卷期：v.16,no.14(July 13, 2004)
- ISSN：1520-5002
文摘
Synthesis and characterization of mono-iron(III)-substituted molybdophosphate, thesolidification as a heterogeneous catalyst, and the oxidative dehydrogenation of 2-propanolwere reported. The catalyst was isolated as Cs2.8H1.2PMo11Fe(H2O)O39·6H2O, and characterized by elemental analysis and X-ray diffraction, infrared, 31P NMR, and ESR spectroscopy.The Fe3+ in Cs2.8H1.2PMo11Fe(H2O)O39·6H2O was incorporated into the molybdophosphateframework while that in Fe3+(2.5 wt %)/Cs3.0PMo12O40 existed as a countercation in arelatively distorted octahedral site. The seven water molecules were desorbed by the thermaltreatment at 63 
C and the cesium hydrogen salt was stable below 210 C. The cesiumhydrogen salt was used for heterogeneous oxidative dehydrogenation of 2-propanol to acetoneand intrinsically has a higher rate than those for the iron-impregnated Fe3+/Cs3.0PMo12O40and Cs3.0PMo12O40 catalysts, showing the effectiveness of isolated iron in the PMo11O397-polyoxometalate on the oxidative dehydrogenation. The data for the stop of the supply ofthe oxygen at the stationary state in the flow experiment showed that acetone was producedby the reaction of 2-propanol with the cesium hydrogen salt. The correlation between intrinsicrates of oxidative dehydrogenation of 2-propanol and reducibility of catalysts, the rateequation of -d[2-PrOH]/dt = k·P2-PrOH0.80·PO2-0.06, and kinetic isotope effects of 1.6-1.9showed that the reduction of the catalyst with the 
-hydrogen elimination from 2-propanolwas the rate-determining step.
C and the cesium hydrogen salt was stable below 210 C. The cesiumhydrogen salt was used for heterogeneous oxidative dehydrogenation of 2-propanol to acetoneand intrinsically has a higher rate than those for the iron-impregnated Fe3+/Cs3.0PMo12O40and Cs3.0PMo12O40 catalysts, showing the effectiveness of isolated iron in the PMo11O397-polyoxometalate on the oxidative dehydrogenation. The data for the stop of the supply ofthe oxygen at the stationary state in the flow experiment showed that acetone was producedby the reaction of 2-propanol with the cesium hydrogen salt. The correlation between intrinsicrates of oxidative dehydrogenation of 2-propanol and reducibility of catalysts, the rateequation of -d[2-PrOH]/dt = k·P2-PrOH0.80·PO2-0.06, and kinetic isotope effects of 1.6-1.9showed that the reduction of the catalyst with the -hydrogen elimination from 2-propanolwas the rate-determining step.