Generation of molecular sieve crystals

zeolite 3a molecular sieve for ethanol drying is a very complex process, and know it has not very clear conclusion. However, whether liquid or solid phase change mechanism, the entire crystallization process generally includes the following four steps: 1. aging, multi-silicate and aluminate and then polymerized, or re-polymeric phosphate and aluminate, i.e., the initial formation of a gel; 2. nucleation, molecular structure directing agent in the core or a certain organization TO4 tetrahedral basic structural unit, around which is formed during the formation of nuclei; 3 nuclei growth; 4. crystal growth and cause secondary nucleation. Therefore, the zeolite synthesis process control is mainly reflected in the choice of the regulation of the initial gel formulation and crystallization conditions on. Aging conducive to the formation of nuclei. Higher initial supersaturation favor crystal nucleation and growth, and a single crystal is prepared zeolite synthesis system requires good control over saturation. Increasing the reaction temperature, and promote the transformation of thermodynamics, but also by changing the concentration of the reactants and over-saturation affect the crystallization kinetics.