Akos Kiss

Introduction of noble metals into small pore zeolites via solid state ion exchange

Abstract A novel method for the preparation of metal containing small pore zeolites is described. The metal is introduced at elevated temperatures by solid state ion exchange. The zeolites obtained by the new method are highly shape selective. As an example, the competitive hydrogenation of an equimolar mixture of hexene-(1) and 2,4,4-trimethylpentene-(1) over various platinum, palladium and rhodium containing 8-membered ring zeolites was studied.

THE HYDROPHOBICITY INDEX – A VALUABLE TEST FOR PROBING THE SURFACE PROPERTIES OF ZEOLITIC ADSORBENTS OR CATALYSTS

The Hydrophobicity Indices (HI) of dealuminated faujasites and ZSM-5-type zeolites are determined by competitive adsorption of toluene and water from the gas phase. HI is a very useful measure for characterizing the hydrophobic or hydrophilic surface properties of molecular sieve materials. For a given zeolite structure, HI increases with the Si/AI ratio and the adsorption temperature. Controlled acid leaching and steaming are prerequisites for the preparation of highly hydrophobic molecular sieve adsorbents or catalysts.