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11-P-27 - The effect of calcination on the isomorphously substituted microporous materials using ozone
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11-P-27- The effect of calcination on the isomorphously substituted microporous materials using ozone D. Mehn a, A. Kukovecz a, I. Kiricsi a, F. Testa b, E. Nigro b, R. Aiello b, G. Daelen c, P. Lentz c, A. Fonseca c and J. B.Nagy c
aApplied Chemistry Department, University of Szeged, H-6720 Szeged, Hungary bOip. di Ingegneria Chimica e dei Materiali, Univ. della Calabria, 1-87030 Rende (CS) Italy r de RMN, Facult6s Universitaires Notre-Dame de la Paix, 61 Rue de Bruxelles, 5000 Namur, Belgium The templating organic molecules or ions have been eliminated by using an oxygen or an ozone treatment. The mild conditions used for the latter preserve quasi intact the various tetrahedral framework elements in B-, Co-, Co, A1-ZSM-5 and in Ga-MCM-22 zeolites.
11-P-28- Aiumination of siliceous zeolites A. Omegna, M. Haouas, G. Pirngruber and R. Prins
Lab. Tech. Chem., ETH-Z~irich, CH-8092 Ziirich, Switzerland (prins@tech. chem. ethz. ch) The post-synthesis incorporation of aluminium into the lattice of pure siliceous zeolite-~ was attempted using aluminium isopropoxide as aluminating agent in a non-aqueous environment. The XRD structural analysis of the Al-grafted materials showed an increase in the unit cell parameters which was associated with the insertion of aluminium into the framework. Quantitative multinuclear NMR investigation showed that the amount of framework aluminium incorporated into the zeolite lattice was related to the concentration of defect sites in the parent Si-[3 zeolite. This indicated that the alumination proceeds through a mechanism which involves the reaction between AI(OPr)3 and silanol groups at defect sites. Calcination after alumination led to the completion of the process, whereby octahedral-coordinated aluminium, (partially) attached to the framework, was transformed into tetrahedralcoordinated framework aluminium.
11-P-29- New hydrophobic Ti-Beta catalyst obtained by silylation and its catalytic performance for olefin epoxidation A. Corma, M.E. D6mine, J.A. Gaona, M.T. Navarro, F. Rey* and S. Valencia.
Instituto de Tecnologia Quimica (UP V-CSIC), Valencia, Spain. frey@itq, upv. es. Silylated Ti-Beta materials show a superior selectivity for epoxidation reactions than analogous fluoride synthesized Ti-Beta. This enhanced yield to the desired epoxide was attributed to the synergetic effect of the basic amine adsorbed on the Ti sites and the presence of silyl groups anchored on the silanol and/or titanol groups of the precursor Ti-Beta catalyst which prevents the oxirane ring opening reaction.
11-P-27- The effect of calcination on the isomorphously substituted microporous materials using ozone D. Mehn a, A. Kukovecz a, I. Kiricsi a, F. Testa b, E. Nigro b, R. Aiello b, G. Daelen c, P. Lentz c, A. Fonseca c and J. B.Nagy c
aApplied Chemistry Department, University of Szeged, H-6720 Szeged, Hungary bOip. di Ingegneria Chimica e dei Materiali, Univ. della Calabria, 1-87030 Rende (CS) Italy r de RMN, Facult6s Universitaires Notre-Dame de la Paix, 61 Rue de Bruxelles, 5000 Namur, Belgium The templating organic molecules or ions have been eliminated by using an oxygen or an ozone treatment. The mild conditions used for the latter preserve quasi intact the various tetrahedral framework elements in B-, Co-, Co, A1-ZSM-5 and in Ga-MCM-22 zeolites.
11-P-28- Aiumination of siliceous zeolites A. Omegna, M. Haouas, G. Pirngruber and R. Prins
Lab. Tech. Chem., ETH-Z~irich, CH-8092 Ziirich, Switzerland (prins@tech. chem. ethz. ch) The post-synthesis incorporation of aluminium into the lattice of pure siliceous zeolite-~ was attempted using aluminium isopropoxide as aluminating agent in a non-aqueous environment. The XRD structural analysis of the Al-grafted materials showed an increase in the unit cell parameters which was associated with the insertion of aluminium into the framework. Quantitative multinuclear NMR investigation showed that the amount of framework aluminium incorporated into the zeolite lattice was related to the concentration of defect sites in the parent Si-[3 zeolite. This indicated that the alumination proceeds through a mechanism which involves the reaction between AI(OPr)3 and silanol groups at defect sites. Calcination after alumination led to the completion of the process, whereby octahedral-coordinated aluminium, (partially) attached to the framework, was transformed into tetrahedralcoordinated framework aluminium.
11-P-29- New hydrophobic Ti-Beta catalyst obtained by silylation and its catalytic performance for olefin epoxidation A. Corma, M.E. D6mine, J.A. Gaona, M.T. Navarro, F. Rey* and S. Valencia.
Instituto de Tecnologia Quimica (UP V-CSIC), Valencia, Spain. frey@itq, upv. es. Silylated Ti-Beta materials show a superior selectivity for epoxidation reactions than analogous fluoride synthesized Ti-Beta. This enhanced yield to the desired epoxide was attributed to the synergetic effect of the basic amine adsorbed on the Ti sites and the presence of silyl groups anchored on the silanol and/or titanol groups of the precursor Ti-Beta catalyst which prevents the oxirane ring opening reaction.