04-O-02-Preparation and catalytic properties of a novel type of zeolites with basic properties

04-O-02-Preparation and catalytic properties of a novel type of zeolites with basic properties

175 0 4 - Isomorphous Substitutions (Friday am) 0 4 - O - 0 1 - Direct synthesis of C u ( I ) - M F I zeolite in the presence o f C u ( I I ) methyl...

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0 4 - Isomorphous Substitutions (Friday am) 0 4 - O - 0 1 - Direct synthesis of C u ( I ) - M F I zeolite in the presence o f C u ( I I )

methylamino complexes as mineralizing and reducing agents S. Valangea, b, F. Di Renzo c, E. Garroned, F. Geobaldo~, B. Onida d and Z. Gabelica a a ENSCMu, GSEC, 3 Rue A. Werner, F-68093, Mulhouse, France, b Present address 9 LACCO, UMR CNRS 6503, ESIP, 40 Av. du Recteur Pineau, F-86022 Poitiers, France, [email protected], ~ ENSCM, 8 rue de l'Ecole Normale, F-34053 Montpellier, France, a Politecnico di Torino, Corso Duca degli Abruzzi 24, 1-10129 Torino, Italy We report for the first time the direct synthesis of a Cu bearing MFI zeolite using amino complexes as mineralizing agents and give experimental evidence of an in-situ reduction of Cu(II) to Cu(I) by methylamine. Cu(I) ions alone never integrate the Al-free MFI framework, while they are partly incorporated in the A1-MFI crystals. Investigation of the nature of the Cu(I) ions in this particular (Cu,A1)-ZSM-5 by UV-vis and FTIR shows that the Cu(I) species are strongly anchored to the MFI framework and are particularly stable and resistant to elution. The kinetics of the Cu(I) incorporation is discussed on the basis of the particular structural model proposed for (Cu,A1)-ZSM-5 0 4 - 0 - 0 2 - Preparation and catalytic properties o f a n o v e l t y p e o f zeolites with basic properties S. Ernst, M. Hartmann and S. Sauerbeck Department of Chemistry, Chemical Technology, University of Kaiserslautern, Germany, [email protected], uni-kl, de Novel basic zeolite catalysts are obtained by ammonia treatment of crystalline, microporous aluminosilicates at temperatures from 700~ to 900~ The resulting materials are active catalysts in the Knoevenagel condensation of benzaldehyde with malononitrile, presumably due to the presence of nitrogen-containing species bound to the crystalline framework. As active sites of the new materials both, terminal -NH2 and bridging -NH-groups can principally be envisaged. A decrease in catalytic activity is observed upon extended exposure to moisture due to hydrolysis of the Si-NH2 groups. The initial catalytic activity, however, can easily be restored by a new ammonia treatment.

04-0-03 - Preparation and characterization of iron-substituted zeolites G. Giordano (a), A. Katovic(a), A. Fonseca (b) and J. B.Nagy (b) (a) Universitdt della Calabria, RENDE (CS), Italy (b) Laboratoire de RMN, FacultOs Universitaires Notre-Dame de la Paix, NAMUR, Belgium Iron is introduced into the framework of three different zeolite-types: MFI, MTW and TON by direct hydrothermal synthesis from alkaline reaction mixtures containing iron complexes (oxalate or phosphate). The synthesis conditions for each zeolite-type and the results on the characterization of the samples by XRD, AAS, thermal analysis, SEM and 29Si-, 13C- and 3~p_ NMR spectroscopy are discussed.