Habit-modifying agents

An overview of additives acting as habit modifier for sodium chloride is given in Table 6.1. More information on habit-modifying agents for other substances is found in Ref. [6]. 

Table 6.1 Habit-modifying agents for sodium chioride [28].

Controlled crystallization, coupled with some form of classifying action in the crystallizer, helps to produce crystals of uniform size. The production of granular crystals, however, may demand the careful control of other conditions of crystallization to modify the crystal habit the rate of cooling, the degree of supersaturation and the pH of the crystallizing solution can exert considerable influence. The deliberate addition of traces of impurity, in the form of active ions or surface-active agents, may also help to produce the right type of crystal. 

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