Synthesis of Zeolite Y in the Presence of Cationic Polymer

Abstract

Synthesis of zeolite Y was studied by using a hydrothermal reaction system including cationic polymer, poly (diallyldimethylammonium chloride) and effects of the polymer on nucleation and crystallization were investigated under a variety of reaction conditions. Xray diffraction technique was used for identification and the determination of zeolite content in the reaction products. The changes of the crystal surface morphology, size and shape of crystals forming during the reaction were studied by using SEM. Detailed observations were also performed for both the reaction products composed of crystal and/or amorphous precursor involving polymer component and their calcined products obtained at 600°C for 24 h. Reaction mechanism was analyzed and apparent activation energies of nucleation and crystallization were determined. A characteristic phenomenon was found in the latter stage of reaction in the cationic polymer present system. The rate of crystallization suddenly drops to a constant rate and then the rate continues until the reaction reaches to completion. It was presumed for polymer effect on crystallization that the cationic polymer chain on the growing crystal surface controls the diffusion of active cluster comprising of anionic chemical species to growing sites of crystal.