Crystallization kinetics growth

In addition to induction time measurements, several other methods have been proposed for determination of bulk crystallization kinetics since they are often considered appropriate for design purposes, either growth and nucleation separately or simultaneously, from both batch and continuous crystallization. Additionally, Mullin (2001) also describes methods for single crystal growth rate determination. 

Crystallization kinetics erystal nueleation, growth, aggregation and disruption kineties (Chapters 5 and 6). 

By means of our experimental method (twin+single crystal kinetics) steady state growth morphology can be predicted as a function of supersaturation and temperature. 

It is shown that while solute concentration data can be used to estimate the kinetic growth parameters, information about the CSD is necessary to evaluate the nucleation parameters. The fraction of light obscured by an illuminated sample of crystals provides a measure of the second moment of the CSD. Numerical and experimental studies demonstrate that all of the kinetic parameters can be identified by using the obscuration measurement along with the concentration measurement. It is also shown that characterization of the crystal shape is very important when evaluating CSD information from light scattering instruments. 

Etherton studied the growth and nucleation kinetics of gypsum crystallization from simulated stack gas liquor using a one-liter seeded mininucleator with a Mixed Suspension Mixed Product Removal (MSMPR) configuration for the fines created by the retained parent seed. The effect of pH and chemical additives on crystallization kinetics of gypsum was measured. This early fundamental study has been the basis for later CSD studies. 

Size-dependent crystal growth is Included in the model because it can be important to describe diffusion limited growth rates or crystal attrition. As discussed in (6,X), the size reduction by attrition can be modelled by an effective growth rate G (L,t) which is the difference between the kinetic growth rate G, (L,tT and an attrition rate G (L,t) ... 

Aspects of nucleation, growth of a single crystal, volume growth, and coarsening processes are discussed in greater depth in Chapter 4. It will be seen that although some of these processes can be quantified well, it is not possible yet to quantitatively predict the kinetics of many of these processes. 

The lateral surface free energy a is a key parameter in polymer crystallization, and is normally derived from crystallization kinetics. In polydisperse polymers, where the supercooling dependence of growth rate is affected both by changing... 

Crystallization kinetics in polymeric systems. Soc. Plastics Engrs. J. 15, Nr. 1 1959, sowie in "Growth and Perfection of Crystals (45). 

Main factors which affect a hydrothermal reaction are the initial eomposition, reaction temperature and time. In mild hydrothermal synthesis, reaction temperatures lower than 240 °C are respected for both safety of high pressure in normal autoclaves and protection of softness of Teflon line. In our specific synthesis system, high temperature favorites the reaction and the most important factor was the base concentration in the initial reaction mixtures. The reaction time associated with reaction temperature affected the reaction. Crystallization kinetic experiment for a typical reaction showed that a reaction time more than lOh gave well-crystallized product and the further crystal growth needed additional time. Table 1 lists the starting reaction compositions and phase identification of products obtained at 240 °C for lOh. 

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