Solvent Effects On The Morpholoy In The Synthesis Of EU-1 Zeolites

Because they are a homogeneous and regular channel structure and larger specific surface area, Molecular sieve materials are widely used in catalysis, adsorption, separation, ion exchange, and other areas of the chemical industry. Molecular sieve materials has become unnecessary materials in industrial production of products. Especially in the field of environmental protection, such as using molecular sieve as catalyst carrier handle NxO catalytic activity is higher than the activity of metal oxide and eliminate SO2. In recent years, the crystallization behavior of molecular sieve in the formation process, growth mechanism and morphology control has become the hot spot of research.This thesis mainly studies the conventional hydrothermal synthesis system, the EU-1 molecular sieve crystallization behavior in the process of synthesis, growth mechanism and influence on the crystal morphology of control conditions. In hydrothermal synthesis, studied the crystallization time impact on EU-1 molecular sieve synthesis, at the beginning of crystallization, using X-ray diffraction (XRD) did not detect the EU-1 zeolite crystals, EU-1 zeolite induction period is about 2 days, with the extension of time, the crystallinity increased gradually, nuclei to crystal growth period is about 4 days.when the crystallization time is more than 6 days, the relative crystallinity not change a lot, but if the time is too long there will be a quartz phase. The impact of the amount of template agent on the EU-1 molecular sieve synthesis have been studied. The effects of rate of charge on the EU-1 molecular sieve synthesis, in order to get pure phase of the EU-1 molecular sieve, ingredients silica alumina ratio should be in a certain range. In order to get EU-1 molecular sieve rapidly and effectively, the rate of charge of Na/Si>0.36, Si/HMBr≥0.11, and Si/Al-25 should be adopted.Add a single small molecule alcohol, the effect of solvent to EU-1 zeolite crystal morphology is not obvious, if adding two or more small molecule alcohol, the ratio of the solvent are not equal at the same time, will produce a dominant solvent, synthetic reaction is mainly affected by the main solvent. When two kinds of solvent’s content is not match, the two kinds of solvents will have great influence on synthesis process. In 190℃ when the crystallization time continue to extend to 48 hours, the preparation of a pure molecular sieve EU-1, the cell is in a state of scattered, when crystallization time continue to grow, the crystallinity of zeolite continue to improve, crystal growth continuously, from the macroscopic form, crystal cell is formed a ellipsoid model of aggregates.