Crystal Shape Engineering
The importance of crystallization in the pharmaceutical, food and fine chemical industries stems from its ability to yield highly pure solid products. Beside the final chemical purity, however, the solid state form, the size and the shape of the resulting particles are of paramount importance for the product quality, because they determine characteristics such as filterability, tabletability, flowability and even bioavailability. Practitioners in these industries are well aware of the fact that crystals can take on a variety of shapes, even for the same chemical substance. Any form of control over particle size and especially shape should allow for the design of improved processes. Until recently, however, the optimization of crystallization processes in terms of particle size and shape has been hindered by a major obstacle: the lack of reliable, fast and quantitative measurement devices, which made online monitoring impossible, hence modeling and optimization unfeasible.
The lecture complements the module devoted to Process Analytical Technology (PAT) by providing insight on how to measure and monitor particles size and shape distributions during crystallization processes.
The lecture will be structured in three parts. The first will be devoted to the introduction of the key concepts about how to deal with size and shape of an ensemble of crystals. The second part will focus on the experimental platform developed and used at ETH Zurich to measure particle size and shape distributions; the pleasures and sorrows of applying this technique will be illustrated with examples. Finally, in the third part we will discuss a possible process to tune the crystal size and shape of crystals in seeded cooling crystallization, using a combination of cooling, milling and heating steps. Also in this case examples will be provided, using both simulations and experiments to assess the process performance.
A short list of key references is provided below:
• Schorsch S., T. Vetter, M. Mazzotti, Measuring multidimensional particle size distributions during crystallization, Chem. Eng. Sci. 77 (2012) 130-142
• Schorsch S., D.R. Ochsenbein, T. Vetter, M. Morari, M. Mazzotti, High accuracy online measurement of multidimensional particle size distributions during crystallization, Chem. Eng. Sci. 105 (2014) 155-168
• de Albuquerque I., D. Ochsenbein, M. Mazzotti, M. Morari, Effect of needle-like crystal shape on measured particle size distributions, AIChE Journal 62 (2016) 2974-2985
Date: Tuesday 31 January 2017
Time: 09:00 – 10:00 hrs
Location: CW507a and b, Cathedral Wing Business School, University of Strathclyde
Book your place online at https://t.co/oBzspOF5L4
You may also be interested in the CORE Network Lecture by Professor Andreas Seidel-Morgenstern - Processes to separate enantiomers https://t.co/1nCbn4HiIC