Study On Growing Zeolite ZSM-5 On Calcined Kaolin By In-situ Synthesis

The Kaolin of China was famous in the world for a good assortment, abundant reserves and a high quality. The kaolin is extensively applied in many aspects, such as petroleum chemical engineering, paper making, function filler and fire-proof materials, etc. It can be used as a supporter to carry catalyst, also used as a raw material for synthesizing zeolite, so is a latent and ideal supporter of in-situ crystallized zeolite molecular sieves.The zeolites in-situ synthesised have an ideal hydrothermal stability, In-situ synthesizing of zeolite can surmount the difficulty of filtration in the industry production and reduce the production cost.This dissertation studied the analytical method of the reactive alumina in the calcined kaolin firstly, and put forward own views on the shortcomings of analytical method which the literature reported. In the end, the content of the reactive alumina in the kaolin was analyzed successfully, making a good foundation for the research on growth of zeolite on/in the kaolin micropores.This dissertation investigates the in-situ ZSM-5 synthesis with the kaolin, and obtain a certain result: the organic or inorganic template,liquid-phase directingagent and solid-phase directing agent were adopted respectively to synthesize,among them the ZSM-5 zeolite could be synthesized completely with solid-phase directing agent method. The characterization of SEM,XRD and FT- IR were carried out. The effect of different crystallization temperatures, the crystallization times, the mole ratios of SiO₂ to Al₂O₃ and the mass of seed crystal on in situ synthesis of the ZSM-5 zeolite was studied. It seems that the lower the temperature is, and the shorter the crystal time is, the more disadvantageous the synthesis of the ZSM-5 zeolite is.Finally, this dissertation put forward some ideas on the in-situ zeolite synthesis by the kaolin, and the mechanism of crystallization of zeolite on/in kaolin was discussed.