SiO<sub>2</sub>-included cesium polyoxotungstate catalysts for oxidation
Keywords:
Polyoxotungstate, Oxidation, Cyclohexane, Hydrogen peroxide, SilicaAbstract
SiO2-included cesium polyoxotungstate catalysts were synthesized by a sol-gel method and characterizied by FTIR, XRD and N2 adsorption isotherms. XRD patterns prove that the cesium polyoxotungstate is uniformly dispersed in the silica network. The catalysts were used in oxidation of cyclohexane with H2O2. The products are cyclohexanol and cyclohexanone. The catalysts prepared by using a copolymer surfactant show higher surface area and exhibit higher activity. These catalysts are truly heterogeneous and can be reused at least 3 times.Downloads
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Shylesh, S., Prinson, P. S. and Singh, A.P. (2007). Chromium-containing small pore mesoporous silicas: Synthesis, characterization and catalytic behavior in the liquid phase oxidation of cyclohexane. Appl. Catal. A. 318 : 128-136.
Mizuno, N. and Misono, M. (1998). Heterogeneous Catalysis. Chem. Rev. 98 : 199-217.
Simões, M.M.Q, Santos, I.C.M.S., Balula, M.S.S., Gamelas, J.A.F, Cavaleiro, Neves, M.G.P. M.S. and Cavaleiro, J.A.S. Oxidation of cycloalkanes with hydrogen peroxide in the presence of Keggin-type polyoxotungstates. Catal. Today. 91-92 : 211-214.
Santos, I.C.M.S., Gamelas, J.A.F., Balula, M.S.S., Simões, M.M.Q., Neves, M.G.P.M.S., Cavaleiro, J.A.S. and Cavaleiro, A.M.V. (2007). Sandwichtype tungstophosphates in the catalytical oxidation of cycloalkanes with hydrogen peroxide. J. Mol. Catal. A : Chem. 262 : 41-47.
Kanjina, W. and Trakarnpruk, W. (2010). Oxidation of cyclohexane and ethylbenzene by hydrogen peroxide over Co-substituted heteropolytungstate catalyst. J. Met. Mater.Miner. 20(2) : 29-34.
Okuhara, T., Watanabe, H., Nishimura, T., Inumaru, K. and Misono, M. (2000). Microstructure of cesium hydrogen salts of 12-tungstophosphoric acid Relevant to novel acid catalysis. Chem. Mater.12(8) : 2230-2238.
Izumi, Y. (1997). Hydration/hydrolysis by solid acids. Catal. Today. 33(4) : 371-409.
Dias, A.S., Lima, S., Pillinger, M., and Valente, A. (2006). Acidic cesium salts of 12- tungstophosphoric acid as catalysts for the dehydration of xylose into furfural. Carbohydr. Res. 341(18) : 2946-2953.
Khder, A.R.S., Hassan, H.M.A. and El-Shall, M.S. (2012). Acid catalyzed organic transformations by heteropoly tungstophosphoric acid supported on MCM-41. Appl. Catal. A : Gen. 411-412 : 77-86.
Kozhevnikov, I.V., Kloetstra, K. R., Sinnema, A., Zandbergen, H.W. and Van Bekkum, H. (1996). Study of catalysts comprising heteropoly acid H3PW12O40 supported on MCM-41 molecular sieve and amorphous silica. J. Mol. Catal. A : Gen. 114 : 287-298.
Jatupisarnpong, J. and Trakarnpruk, W. (2012). Transition metal-substituted polyoxometalates loaded MCM-41 as catalysts in the oxidation of cyclohexane and cyclooctane with H2O2. Mendeleev Commun. 22 : 152-153.
Rocchiccioli-Deltcheff, C., Amirouche, M., Herve, G., Fournier, M., Che, M. And Tatibouet, J.M. (1990). Structure and catalytic properties of silica-supported polyoxomolybdates.II. Thermal behavior of unsupported and silica-supported 12-molybdosilicic acid catalysts from IR and catalytic reactivity studies. J. Catal. 126 : 591-599.
Izumi, Y., Hisano, K. and Hida, T. (1999). Acid catalysis of silica-included heteropolyacid in polar reaction media. Appl. Catal. A : Gen. 181 : 277-282.
Molnár, A., Keresszegi, C. and Török, B. (1999). Heteropoly acids immobilized into a silica matrix : characterization and catalytic applications. Appl. Catal. A : Gen. 189 :217-224.
Seki, Y., Min, J.S., Misono, M. and Mizuno, N. (2000). Reaction mechanism of oxidation of methane with hydrogen peroxide catalyzed by 11-molybdo-l-vanadophosphoric acid catalyst precursor. J. Phys. Chem. B. 104 : 5940-5944.
Peng, G., Wang, Y., Hua, C., Wang, E., Feng, S., Zhou, Y., Ding, H. and Liu, Y. (2001). Heteropolyoxometalates which are included in microporous silica, CsxH3−xPMo12O40/SiO2 and Cs yH5−yPMo10V2O40/SiO2, as insoluble solid bifunctional catalysts : synthesis and selective oxidation of benzyl alcohol in liquid-solid systems. Appl. Catal. A : Gen. 218 : 91-99.
Balbinot, L., Schuchardt, U., Vera, C. and Sepaveda, J. (2008). Oxidation of cyclohexanol to epsilon-caprolactone with aqueous hydrogen peroxide on H3PW12O40 and Cs2.5H0.5PW12O40. Cat. Commun. 9 : 1878-1881.
Simoes, M.M.Q., Conceic, C.M.M., Gamelas, J.A.F., Domingues, P.M.D.N., Cavaleiro, A.M.V., Cavaleiro, J.A.S., Ferrer-Correia, A.J.V. and Johnstone, R.A.W. (1999). Keggin-type polyoxotungstates as catalysts in the oxidation of cyclohexane by dilute aqueous hydrogen peroxide. J. Mol. Catal. A : Chem. 144 : 461-468.
Dias, J.A., Caliman, E. and Dias, S.C.L. (2004). Effects of cesium ion exchange on acidity of 12-tungstophosphoric acid. Micropor. Mesopor. Mat. 76(1-3) : 221-232.
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