Free Access
J. Phys. IV France
Volume 11, Number PR10, Décembre 2001
Journées d'Étude des Équilibres entre Phases
Page(s) Pr10-71 - Pr10-77
Journées d'Étude des Équilibres entre Phases

J. Phys. IV France 11 (2001) Pr10-71-Pr10-77

DOI: 10.1051/jp4:20011009

Effect of the polymorphic form of the seeds on the preferential crystallisation

L. Courvoisier, C. Gervais, L. Mignot, M.-N. Petit and G. Coquerel

Unité de Croissance Cristalline et de Modélisation Moléculaire (UC2M2), UPRES EA 2659, IRCOF, Université de Rouen, rue Tesnière, 76821 Mont-Saint-Aignan cedex, France

The 5(4'-methylphenyl)-5-methyl-hydantoin (17H) is known to crystallise in two polymorphic forms, α and β. Crystallographic parameters and molecular structure of the 17H polymorphs (orthorhombic and monoclinic forms) were first investigated. Then, the main kinetical parameters of the polymorphic transition are presented. The transition rate is so low that different seeding experiments can be undertaken. Seeded Isothermal Preferential Crystallisation (SIPC) method was applied to perform the separation of the enantiomers at a 2 L scale with two types of seeds, monoclinic and orthorhombic. Orthorhombic form was never obtained in the crops but the physical parameters of the crystals produced (size, form, . ..) were strongly affected by the nature of the polymorph seeds.

© EDP Sciences 2001