Patent ID: 7402297

Claim:
A method for preparing a molecular sieve having the CHA crystal structure and a mole ratio of greater than 50:1 of (1) silicon oxide, germanium oxide and mixtures thereof to (2) aluminum oxide, iron oxide, titanium oxide, gallium oxide and mixtures thereof said method comprising: A. forming an aqueous reaction mixture comprising a composition in terms of mole ratios falling within the following ranges: YO 2 /W a O b 400–∞ OH—/YO 2 0.19–0.52 Q/YO 2 0.15–0.25 M 2/n O/YO 2 0.04–0.10 H 2 O/YO 2 10–50 wherein Y is silicon, germanium or mixtures thereof, W is aluminum, iron, titanium, gallium or mixtures thereof, a is 1 or 2, b is 2 when a is 1 or b is 3 when a is 2; M is an alkali metal or alkaline earth metal, n is the valence of M, and Q is a cation derived from 1-adamantamine, 3-quinuclidinol or 2-exo-aminonorbornane; and B. maintaining said aqueous mixture under sufficient crystallization conditions until crystals are formed wherein the molecular sieve is prepared in the absence of fluorine.