by a zeolitic crystalline aluminosilicate compensated in more than 90 by alkaline cations having a pore diameter of more than 6 5 angstroms application_number US 47190283 A description the carrier comprises a zeolitic crystalline aluminosilicate or molecular sieve it is essential for the dehydrocyclization that the molecular sieve serving as a carrier have only a slight acidity no acidity or a slight basicity the zeolite must have its cationic sites of exchange exchanged with more than 90 of alkaline cations the other cations introduce a certain acidity either because they are multivalent and thus create acid sites or because they can be reduced or decomposed under the conditions of the catalysis the reduction or decomposition corresponding to the formation of protons on the zeolite it is evident that the pores of the alkaline zeolite must have a size at least equal to the dimensions of the benzene molecule the zeolites which are useful are the faujasites x and y zeolite l zeolite omega and zeolite zsm 4 these zeolites can be used in their form as synthesized except for zeolite omega and zsm 4 which contain alkylammonium cations which must be replaced by alkali metal cations by the methods known to those skilled in the art such as thermal decomposition followed by neutralization by an alkali metal basic material it is also possible to exchange the snythesis cations by other alkali metal cations and the zeolites in question can therefore contain lithium sodium potassium rubidium and or ceesium among the zeolites the preferred carrier is zeolite l which provides exceptional yields.