Patent ID: 8409546

Claim:
A process for the preparation of zeolites having B-CHA framework structure and a composition comprising the molar ratio (n SiO 2 ) : B 2 O 3 , wherein n is at least 10, the process comprising (i) preparation of an aqueous solution containing at least one source for B 2 O 3 , at least one source for SiO 2 , at least one source of seeding crystals of chabazite structure, at least one organic structure directing agent (SDA) other than Tetramethylammonium hydroxide (TMAOH), acting as a template for the B-CHA structure, and Tetramethylammonium hydroxide (TMAOH), wherein the SDA or mixtures thereof are employed in such amounts that the aqueous solution in (i) exhibits a molar ratio of SDA : TMAOH of 0.01 to 5; (ii) hydrothermal crystallization of the aqueous solution according to (i); wherein the ratio of the molar ratio of SiO 2 : B 2 O 3 of the gel composition to the molar ratio of SiO 2 : B 2 O 3 of the crystalline product having the chabazite structure is greater than 0.5; and B-CHA is essentially free of alkali metal and/or alkaline earth metal.