Abstract (EN):
In the present work the effect of CaCl2 on sucrose crystallization at 35°C was analysed. This study was divided in three parts: the effect of impurity concentration on global crystallization rate; the impurity adsorption into the crystal; and the effect of impurity on growth rate of the crystal faces. The influence of impurity concentration on crystallization rates was studied in a fluidized bed crystallizer. By Potentiometric titration it was possible to quantify the transfer of the impurity into the crystals and to find a connection between the crystal growth rate and the impurity adsorption. To study the effect of the impurity on the crystal faces a growth cell connected to a microscopic was used. The combination of these techniques allowed us to understand better how the impurities work. In the present study, the increase of impurity concentration decreases the crystal growth rate. This effect is higher at lower crystal growth rates. According to potentiometric results, this is because the relative impurity adsorption is superior at these conditions.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
7