Temperature effects on the crystallization kinetics of size-dependent systems in a continuous mixed-suspension mixed-product removal crystallizer

Abstract

This study examined the nucleation and growth behaviors of potassium alum crystals in a well-mixed continuous crystallizer. Crystal growth rates are size dependent and surface integration controlled.The higher temperatures enhance the growth rate but depress the nucleation rate. The interface supersaturation, which is identical with the overall supersaturation in this study, decreases as the temperature is increased under the constraints of constant retention time and magma density. The predicted kinetic behaviors influenced by temperature were found to be in agreement with those i f experimental results.

Synergetic effects of temperature and magnetic field on the aragonite and calcite growth

“…This is probably true because more aragonite would be formed by nucleation at a higher temperature, as reported by Wray and Daniels (1957). Nevertheless, the temperature effects were observed for other systems without changing the crystal morphology, such as potassium alum (Wu et al, 1991;Rousseau and Woo, 1980) and citric acid (Sikdar and Randolph, 1976). Thus, the temperature might have dual effects on the growth of aragonite seeds.…”

“…Nevertheless, almost all of the clusters existing in the supersaturated solution were transformed into those available for aragonite growth under magnetizing for a long period of time. At higher temperatures, the clusters adsorbed on the crystal surface were more active in causing a higher surface-integration rate, just like the systems of potassium alum and citric acid (Sikdar and Randolph, 1976;Wu et al, 1991). For the case without the treatment of magnetic field, none of the clusters were available for aragonite growth at room temperature.…”

CRYSTALLIZATION KINETICS AND PRODUCT PURITY OF Α-Glutamic ACID CRYSTAL

“…The measured solubility at 15°C was 0.716 g hydrate/l0 g water, which is about 6.4% lower than the value calculated by Eq. (13). Other values at different temperatures are shown in Figure 2.…”

“…The major component of the apparatus is a cooling CMSMPR crystallizer with an active volume of 5.7 x 10-3 m", which is essentially the same as that described in the report by Wu et at. [13], where details of the experiment procedures can also be found. A brief description of the procedure is presented below.…”

“…10g(C*) = -0.377 + 0.0174T (13) Solubility data were checked in this experiment following the Sakata's method i.e., saturated solution in equilibrium with excess crystals. The measured solubility at 15°C was 0.716 g hydrate/l0 g water, which is about 6.4% lower than the value calculated by Eq.…”