Influence of silica and alumina source materials on the physicochemical characteristics of crystalline zeolite beta

Abstract

Abstract The influence of different silica sources such as silica sol and fumed silica on the physochemcial characteristics of well crystalline zeolite beta was studied as a function of variation in alumina sources viz. sodium aluminate and aluminium isopropoxide. Furthermore, the effect of templating organocation source on the crystallization kinetics and characteristics of fully crystalline beta zeolite was also investigated. The detailed characterization was carried out by using powder XRD, TG/DTG, 27A1 and 29Si MASNMR, XPS, Chemical analysis and low temperature nitrogen adsorption. From kinetics of crystallization data obtained from various systems containing different combination of source materials, TEA OH, silica sol and sodium aluminate are found to be most efficient source materials. The weight loss due to water, occluded TEAOH/Br , TEA+ and oxidative decomposition of organic materials occluded in the materials were compared as a function of variation in the source materials.The crystalline beta phase obtained using fumed silica and aluminium isopropoxide was found more susceptible for the dealumination during calcination. The crystalline beta phase prepared by using silica sol and sodium aluminate as a source of silica and alumina respectively showed superiority in the uniformity of aluminium distribution and possesses higher surface area in the present studies.