Preparation Of ZSM-5Zeolite With Coal Kaolin And The Study On Synthesis Mechanism

On the basis of the development and application of calcined coal kaolin, compoundingZSM-5zeolite and the synthesis mechanism on ZSM-5zeolite, we have conducted thecomprehensive research on the synthesis of ZSM-5zeolite, which using kaolin as raw material.In the experiment, XRD,XRF, SEM, XPS, FTIR and other modern analyzed techniques wereused to characterize the synthesis products. The main contents are as follows:Through analyzing the composition structure of wanbei calcined coal kaolin, we can usethe way of calcination activation and acid leaching to improve the silica-alumina ratio in kaolin.This kaolin can become the raw materials in the reaction of ZSM-5zeolite hydrothermalsynthesis. The condition of calcinations is: add1%solid NH4Cl and calcine the mixture forone hour in the temperature of750℃; the condition of acid leaching is: temperatures in95℃for45minutes. Through the depth study on basicity, template, crystallization temperature,crystallization time, seed crystal and so on, we find the best condition to compound ZSM-5zeolite using kaolin as the raw material. That is: Na2O/SiO2=0.12；C4H11N/SiO2=0.25；H2O/SiO2=30；ageing time is12h at room temperature, crystallization time is60h at thetemperature of170℃. And I have discussed the effect of different template agent:n-butylamine﹥ethyl alcohol﹥ammonium hydroxideThe forming process of ZSM-5zeolite have analyzed synthetically. Firstly, the samplewas processed by silicon alkylation, then gas chromatography was used to study variousaggregation states of silicate. Secondly, the relationship between the concentration of silicateions or aluminum acid ions and the reaction time was worked out by potassium fluosilicatevolumetric method and EDTA complexometric method. Finally, the formation process ofZSM-5zeolite was speculated combined with the SEM, XRD, XPS and other modernanalytical techniques.This paper for the later development and utilization of calcined coal kaolin and synthesisof different silica-alumina ratio of ZSM-5zeolite which used in more fields has a very goodreference value.