Secondary crystal growth

Finally, zeolite nanoparticles have been used as building blocks to construct hierarchical self-standing porous stmctures. For example, multilayers of colloidal zeolite crystals have been coated on polystyrene beads with a size of less than 10 p,m [271,272]. Also, silicalite-1 membranes with a thickness ranging from 20 to several millimeters and controlled mesoporosity [273] have been synthesized by the self-assembly of zeolite nanocrystals followed by high-pressure compression and controlled secondary crystal growth via microwave heating. These structures could be useful for separation and catalysis applications. 

Garside, J. and Larson, M.A., 1978. Direct observation of secondary nuclei production. Journal of Crystal Growth, 43, 694. 

Secondary nucleation is essentially a crystal growth process. Secondary nucleation occurs by the deposition of a stem of the polymer molecule on a preexisting crystal-face as shown in Figure 15. The overall rate of this process is given by the following expression [58],... 

Another important development which altered our view of crystallization processes was the realization of the importance of secondary nucleation due to contact between crystals and the impeller and vessel. Secondary nucleation of this type has been shown (2-6) to often have a dominant role in determining crystallizer performance. Our understanding of crystal growth, nucleation, fluid mechanics and mixing have all greatly improved. A number of review (2r 101 have appeared in recent years which describe the advances in these and... 

Variation of Shape Factor. Three typical variations In the shape factor of MgSOi 71120 crystal are shown In Figure 1. The factors show the results obtained from three experiments of crystal growth In the solution without gas admittance at a supersaturation degree (AC) of 1.78 kg m , and a temperature of 298.2 K. In this solution, secondary nuclei(4) were hardly found. The curves connecting the points In the figure were determined by Fourier series equations to... 

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