Chemistry

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11 March 2020

Research Seminar: Flow crystallisation - controlled self-assembly and in situ structural analysis

Presented By Dr Karen Robertson (University of Nottingham)

About this event

Abstract

Flow technologies have inherently homogeneous mixing and temperature control and scalability. This makes them ideal for the production of materials which may present a range of structures dependent on the precise production conditions. When it comes to the active precipitation of solid materials in flow environments, there are unique challenges to be addressed such as suspension and mixing of solids, blockages and encrustation. Great opportunities of flow environments include access to detailed monitoring of transient events in situ and non-invasively.

A range of flow crystallisers will be presented to address the challenges of flow synthesis and crystallisation showing how each apparatus can provide control on different scales (time and particle size). By employing these crystallisers we have exacted control in terms of polymorphic purity, crystal size and shape for organic materials (pharmaceuticals),1 discrete organometallic complexes and coordination polymers (spin-crossover materials).2 Using in situ structural analysis (powder and single crystal X-ray diffraction and Raman spectroscopy),3 we follow what is crystallising as it is crystallising enabling further understanding and control of the crystallisation process, uncovering polymorphic transitions and verifying relative polymorphic stabilities.

 

1.         Robertson, K.;  Flandrin, P.-B.;  Klapwijk, A. R.; Wilson, C. C., Design and Evaluation of a Mesoscale Segmented Flow Reactor(KRAIC). Crystal Growth and Design 2016, 16, 4759-4764.

2.         Robertson, K.;  Flandrin, P. B.;  Shepherd, H. J.; Wilson, C. C., (Fe(Htrz)2(trz)) (BF4) nanoparticle production in a milli-scale segmented flow crystalliser. Chimica Oggi-Chemistry Today 2017, 35 (1), 19-22.

3.         Pallipurath, A. R.;  Flandrin, P. B.;  Wayment, L. E.;  Wilson, C. C.; Robertson, K., In situ non-invasive Raman spectroscopic characterisation of succinic acid polymorphism during segmented flow crystallisation. Molecular Systems Design & Engineering 2020, 5 (1), 294-303.