Survey of Crystal Habit Modification in Solution

Abstract

During these last years, crystal habit modification has been widely used for many purposes in Industrial Crystallization. The reader will find in certain books |1–12| and in some earlier review papers |13 – 18| several hundreds of references concerning habit change examples and theoretical interpretations. As in Chemical Engineering people are daily interested in obtaining different crystal habits, we shall try to summarize here the main factors involved in crystal habit modification, with the aid of a few recent and representative studies. To avoid confusion, we can just recall that, if the habit is defined as the overall shape of the crystal made up of a whole of {hkl} forms, the habit change /nay be understood in two ways. It is either a change in the relative development of the already existing {hkl} forms, or the appearance of some new {h’k’l»}forms.