Preparation of crystalline aluminosilicate zeolite, and its product

Claim 1

A process for producing a crystalline aluminosilicate zeolite characterized by having (a) a silica/alumina mole ratio of from 10 to 100, (b) X-ray lattice distances d shown in Table A of the specification, (c) a specific n-hexane adsorption, as measured on a precisely weighed sample of the zeolite which has been calcined at 450° for 8 hours until the pressure reaches 50±1 mm Hg, and maintained at 20±1° C. for 2 hours of at least 0.07 g/g, (d) a (2-methylpentane/cyclohexane) adsorption ratio of from 1.2 to 1.6, and (e) when the intensity (I o ) of the X-ray diffraction peak at d(Å)=3.86 is taken as 100, the relative intensity (I/I o ) of the X-ray diffraction peak at d(Å)=3.83 is at least 70, which comprises maintaining a silica source, an alumina source, and a seed zeolite selected from the group consisting of zeolite ZSM-5 and zeolites having said characteristics (a)-(e) inclusive, specified above, in an aqueous solution containing 1 to 200 millimoles, per gram of said zeolite, of an alkali metal hydroxide, in such proportions that the silica source, the alumina source and the alkali metal hydroxide satisfy the following mole ratios in terms of SiO 2 , Al 2 O 3 and OH-: SiO.sub.2 /Al.sub.2 O.sub.3 =5-100 OH-/(SiO.sub.2 +Al.sub.2 O.sub.3 =about 0.5-1 and OH-/H.sub.2 O=0.005-0.05, and under such temperature, pressure and time conditions as to produce a crystalline aluminosilicate zeolite.