CATALYST COMPRISING AN AFX-STRUCTURE ZEOLITE PREPARED FROM A MIXTURE OF FAU ZEOLITES AND AT LEAST ONE TRANSITION METAL FOR SELECTIVE REDUCTION OF NO_X

摘要

The invention relates to a method for preparing a catalyst containing an AFX-structure zeolite and at least one transition metal, said method comprising at least the following steps: i) in an aqueous medium, mixing of at least two FAU-structure zeolites, an organic nitrogen-containing compound R, at least one source of at least one alkali and/or alkaline-earth metal M, until a homogeneous precursor gel is obtained; ii) hydrothermal treatment of said precursor gel in order to obtain a crystallized solid phase, known as the "solid" phase; iii) at least one ion exchange with a transition metal; and iv) thermal treatment. The invention also relates to the catalyst that can be obtained or obtained directly by the method and to the use thereof for the selective reduction of NOx.