Analysis of the interplay between agitation-induced damage and crystal growth in suspension crystallization by means of three-dimensional shape analysis

• Applicant: Professor Dr.-Ing. Heiko Briesen
• Subject Area: Chemical and Thermal Process Engineering ; Mechanical Process Engineering
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 456595618

Crystallization is a frequently used unit operation for product formulation and purification of fine chemicals, food and active pharmaceutical ingredients. The shape of crystals is an important process parameter and also a quality criterion of the crystalline product. For example, the shape of crystals has a decisive influence on the bioavailability of crystalline active pharmaceutical ingredient or on the activity of catalysts. During the manufacturing process, the shape of the crystals also influences the crystallization process itself and subsequent process steps such as washing, drying, or centrifugation. State of the art methods for crystal shape analysis use 2D imaging techniques. Using such methods, the size of crystals can be well estimated. However, their ability to determine the 3D shape of crystals is inherently limited. This is especially the case when complex shapes, such as those caused by breakage, attrition, or agglomeration, are to be characterized. In previous work we developed methods to describe the shape of single and agglomerated crystals in 3D. Besides agglomeration, breakage and attrition are two very common phenomena occurring during crystallization. In the present project, methods will be extended to also cover the shape of damaged crystals (breakage and attrition). These methods will then be used to investigate the influence of breakage and attrition on the development of the shape of crystals through crystal growth. The knowledge gained will be used to model the shape of crystals in a crystallization process taking into account crystal growth, breakage and attrition.

• DFG Programme: Research Grants