Crystalline zeolite composition ECR-31 and process for its preparation

Claim 2

A synthetic crystalline zeolite composition having the formula in terms of mole ratios M.sub.2/n O: Al.sub.2 O.sub.3 : xSiO.sub.2 "(y(H.sub.2 O, NH.sub.3) where n is the valence of metal M, x is between 3 and 10, and y is between 0 and 14 and characterized having a representative x-ray diffraction pattern (cu K.sub.α radiation) with major lines shown in Table 1.

Claim 3

The zeolite of claim 1 wherein M is a mono-, di- or trivalent metal cation selected from Group I to III of the Periodic Table, or mixtures thereof.

Claim 4

The zeolite of claim 1 having an oxide composition in the range: 0.9 to 1.2 K.sub.2 O: Al.sub.2 O.sub.3 : 3.0 to 6.0 SiO.sub.2. 4.

Claim 5

A process for preparing the crystalline zeolite of claim 1 where M is K and n is 1, which comprises: (a) preparing a reaction mixture comprising water, a source of silica alumina gel, KOH and ammonia, said reaction mixture having a composition, in terms of mole ratios of oxides, within the following ranges: ______________________________________ SiO.sub.2 /K.sub.2 O 1.2 to 1.6 SiO.sub.2 /Al.sub.2 O.sub.3 3.0 to 14 NH.sub.3 /Al.sub.2 O.sub.3 40 to 140 H.sub.2 O/Al.sub.2 O.sub.3 85 to 300 ______________________________________ (b) maintaining the reaction mixture at between about 70° C. and 150° C. under autogenous pressure for a sufficient period of time to form crystals of the zeolite.

Claim 6

The process of claim 4 wherein during step (b) the reaction mixture is agitated to maintain substantial homogeneity thereof.

Claim 7

The process of claim 4 wherein the crystalline zeolite product has a composition in the range: 0.9 to 1.1 K.sub.2 O: Al.sub.2 O.sub.3 : 3 to 4.5 SiO.sub.2.

Claim 8

The process of claim 4 wherein the silica-alumina gel is partially dried.

Claim 9

The process of claim 4 wherein the source of silica-alumina gel is a spray dried amorphous silica-alumina particulate, exchanged with ammonium cations, and having a (Na,K) 2 O content less than 3 wt % on a dry basis.

Claim 10

The process of claim 4 wherein prior to step (b) microcrystals of a zeolite are added to the blended reaction mixture in an amount of from 0.1 to 10% by weight based on silica and alumina.