Preparation of zeolite P by desilication and recrystallization of zeolites ZSM-22 and ZSM-35

This work describes an original way to obtain zeolite P through dissolution and recrystallization of zeolites ZSM-22 and ZSM-35. The starting zeolites, in their H-form, were subjected to desilication and recrystallization in a single step in the presence of a NaOH solution at 100 °C for 20 h. The X-ray diffraction (XRD) results confirmed the formation of crystalline zeolite P. Specific surface areas from 20 to 70 m2/g were obtained with mesoporous volumes between 0.03 and 0.22 cm3/g. Scanning Electron Microscopy (SEM) micrographs showed that the obtained materials had been formed by agglomerates of nanosized crystallites.