Dealumination of zeolite Y with SiCl4: a two-step reaction

Evidence is presented that the dealumination of zeolite Y with SiCl4 occurs in two distinguishable reaction steps; in the first step, lattice-attached ‘SiCl3’ species and the chloride salt of the charge compensating cation are formed, followed secondly by the isomorphic substitution of Al for Si and the subsequent formation of chloro–aluminium complexes.