PROCESS FOR THE SYNTHESIS OF A ZEOLITE OF STRUCTURAL AFX TYPE OF VERY HIGH PURITY IN THE PRESENCE OF AN ORGANIC NITROGEN STRUCTURANT

摘要

The invention relates to a process for the preparation of an AFX structural zeolite comprising at least the following steps: i) the mixing in an aqueous medium of a zeolite of structural type FAU having a molar ratio SiO 2 (FAU) / Al 2 O 3 ( FAU) between 6.00 and 200, inclusive limits, of a nitrogenous organic compound R, of at least one source of at least one alkali metal and / or alkaline earth metal M, the reaction mixture having the following molar composition (SiO2 (FAU)) / (Al2O3 (FAU)) between 6.00 and 200, H2O / (SiO2 (FAU)) between 1.00 and 100, R / (SiO2 (FAU)) between 0, 01 to 0.60, M2 / nO / (SiO2 (FAU)) between 0.005 to 0.45, limits included, until a homogeneous precursor gel is obtained; ii) the hydrothermal treatment of said precursor gel obtained after step i) at a temperature between 120 ° C and 220 ° C for a period of between 12 hours and 15 days.