Experimental Investigation of Crystal Shape Evolution During Growth and Dissolution

Controlling crystal morphology is a hot topic in current research on crystalline materials for diverse industrial applications. In this connection, experimental detection of polymorphs through on-line measurement of crystal morphology in a crystallizer is a problem of crucial interest. XRD and Raman Spectroscopy are generally accepted as a primary method to identify polymorphs. We present evidence of a new, strikingly simple and inexpensive method of identifying polymorphs through computer-aided analysis of images produced with a Confocal microscope. This methodology has the following features.

• A software with an automated program for polymorph detection integrated with a Confocal microscope which can be used for on-line monitoring and control of particle shape, size and polymorph content.
• Different polymorphs can be identified by recognizing inter-planar angular patterns specific to a given polymorph. It yields the absolute amounts of different polymorphs present in a population of crystals.
• It has the potential for on-line measurement of 2D and 3D crystals of complex shapes.

Consequently, this methodology can:

• Replace currently used FBRM (focused-beam reflectance measurement), digital video imaging and microscopy based sensors that have limitations with real shapes.
• Eliminate the need for multiple sensors currently used in industry.