Synthesis and Shape-Selective Properties of ZSM-22 

 -  Applied Catalysis, 48(1), p.137-148, 1989 .
<br/><br/> Zeolite ZSM-22 was synthesized in the presence of diaminohexane. From the characterization of the synthesized material, it could be deduced that the organic compound acts as a pore-filling agent during synthesis. The H-form of the zeolite contains surface hydroxyl groups, which are identical with those found in H-ZSM-5 and other high-silica zeolites. The intracrystalline voids of ZSM-22 were characterized with catalytic test reactions. The constraint index was determined and the n-decane test applied. ZSM-22 catalytically behaves as a ten-membered ring zeolite, with an effective pore size slightly smaller than that of ZSM-5. As a result of shape-selective effects, n-decane isomerization products are mainly branced at the ends of the hydrocarbon chain.