Zeolites are crystalline microporous minerals, built up of silicon, aluminum and
oxygen atoms. A brief historical overview and a short general introduction on the
structure and application of zeolites are given. The concept of catalysis is introduced
and the use and operation of zeolites as active and selective catalysts in hydrocarbon
reactions is exemplified. In view of the further contents of this thesis, short
introductions on the occurrence and measurement of adsorption, diffusion and coke
formation on zeolites are presented.