Crystalline isotactic zeolites and their preparation

A process for the preparation of a crystalline isotactic zeolite of the composition

• 2/nR.W.sub.2 O.sub.3.mYO.sub.2.PH.sub.2 O
• where R is an organic amine having a lower basicity than that of an alkali base or of a quatenary nitrogen base and n is the number of amine groups in the amine molecule, W is selected from the group comprising B, Al, Ga, Fe or any combination thereof, Y is selected from the group comprising Si, Ge or any combination thereof, and m is ##EQU2## where L.sub.R is the length of the amine molecule in A, K is a constant having a value of 4, p is a number of from 0 to 160 and the crystalline isotactic zeolite material exhibits one or more of the following diffraction lines d(A)=11.1.+-.0.3/10.0.+-.0.25/3.85.+-.0.1/3.71.+-.0.1/3.54.+-.0.07 from a mixture of YO.sub.2 and W.sub.2 O.sub.3 by hydrothermal crystallization at from 100 to 200.degree. C., wherein the crystallization is carried out in the absence of an alkali metal base, alkaline earth metal base and quaternary nitrogen base and their intermediates, with the aid of an organic amine, the molar ratio of YO.sub.2 to W.sub.2 O.sub.3 in the reaction mixture being brought to a value, depending on the chain length L.sub.R of the organic amine, which is appropriate for the formation of the isotactic zeolite, the molar ratio H.sub.2 O/amine being from 0.4 to 100 and molar ratio amine/Al.sub.2 O.sub.3 being from 5 to 400.