Transformation of MCM-22(P) into ITQ-2: The role of framework aluminium

The aim of this paper is to investigate systematically the formation of ITQ-2 from different MCM-22(P) materials.Particular attention has been devoted to understanding how each delamination step influences the final ITQ-2 materials. In order to characterize the intermediate products of the delamination steps, various types of analysis have been carried out: XRD, 27Al-, 29Si-, and 13C-MAS NMR, DSC-TG and chemical analyses. It has been confirmed that the delamination process is favoured by the decreasing aluminium concentration of parent materials. The investigation carried out has shown that aluminium always remains in tetrahedral coordination, in both the ITQ-2 and MCM-22 (P) phases probably because it is protected, during the delamination process, by the organic cation used in the MCM-22(P) synthesis.