Process for preparation of faujasite zeolite

摘要

A faujasite zeolite of a high purity and a desired silica/alumina ratio is prepared by crystallizing at an elevated temperature a reaction mixture comprising a silica source, an alumina source, and an alkali metal source, wherein a transparent faujasite germ solution obtained by mixing and aging aqueous alkali metal silicate solution, an aqueous alkali metal aluminate solution and an aqueous alkali metal hydroxide solution is made present in the reaction mixture. The faujasite germ solution has an oxide molar composition represented by the following molar ratios: SiO2/Al2O3=8 to 14, M2O/Al2O3=7 to 30, and H2O/M2O=10 to 14, wherein M represents an alkali metal. The amount of the faujasite germ solution is 1 to 30 wt. % as Al2O3 based on the faujasite zeolite.