Wladimir Reschetilowski

On the Bifunctional Action of Modified Zeolites Y Containing Nickel

Abstract Catalytic properties of modified zeolites Y containing nickel were characterized by the conversion of n-hexane, the reaction of cyclohexane, and the hydrogenolysis of ethane, respectively. The changes in the catalytic properties resulting from the modification of zeolite acidity suggest that there exists a direct interaction between the metal and the support, which is particularly evident in samples prepared by impregnation. Increasing acidity of the support leads to a decrease and finally to the suppression of both dehydrogenation and hydrogenolysis activity of the supported Ni/HNa-Y catalyst. At the same time the selectivity in skeletal isomerization is improved.

Chemical and Catalytic Properties of ZSM-5 Type Boroaluminosilicates

Abstract Isomorphous incorporation of boron into ZSM-5 and the influence on the properties of the products were investigated. Acidity and catalytic activity in paraffin cracking reactions strongly depend on the concentration of framework aluminium atoms. Incorporated boron perfectly detectable by 11B MAS NMR influences shape selectivity only.

PIGE and PIXE analyses of pentasil type boroaluminosilicates

The elemental composition of various synthetic crystalline sodium-boroaluminosilicates, especially the Al content and the silicon to aluminium bulk ratio, were determined by means of the combination of PIGE (Proton-Induced Gamma-Ray Emission Spectrometry) and PIXE (Proton-Induced X-Ray Emission Spectrometry). Light elements (B, O, Na, Al) were determined by means of gamma-ray emission. Proton-induced X-ray emission provided information on heavy elements present down to impurities. The Si/Al ratios, which mainly determine the catalytic and adsorptive properties of the zeolites, are compared with those obtained with other methods (EPMA, H2O sorption capacity) and show good agreement.