Speaker: Dr. Anne Hartwig

Date and Time: 10:00-11:30am, October 17, 2017

Venue: Meeting Room 223, IPE Building

Title：Photon Density Wave Spectroscopy as a New Approach for Monitoring the Cooling Crystallization from Highly Concentrated Solutions

Abstract：
Photon Density Wave (PDW) spectroscopy characterizes the optical properties of highly turbid liquids in-line and in real-time.In total,PDW spectroscopy measurements result in the dilution free quantification of the mean particle diameter,the absorption coefficient and the reduced scattering coefficient. Besides particle sizing,PDW spectroscopy can be applied for monitoring crystallization processes due to its capability to detect changes in the liquid phase as well as the formation of solid particles and their growth.
Cooling crystallization of lactose as model substance was performed in an automated lab reactor and different cooling rates as well as seeding strategies were applied. Lactose was dissolved in deionized water as well as in whey to generate highly turbid dispersions,suitable for PDW spectroscopy.Dissolution and nucleation were investigated in the relevant temperature range which was defined by the solubility curve.
The dependency of the crystallization behavior on the applied cooling rate and seeding strategy was monitored and analyzed by PDW spectroscopy and it will be shown that PDW spectroscopy is asuitable process an alytical technology (PAT)for monitoring cooling crystallization processes.

About the speaker:
Anne Hartwig. Her diploma thesis focused on the fatty acid profile in aqueous humour of infected eyes. After her thesis, she joined the chair of Prof.Ulrich, Center for Engineering Sciences, Thermal Process Engineering at the University of Halle-Wittenberg. In ther PhD thesis she developed new processes for the in situ encapsulation of liquids by means of crystallization. After her PhD she joined the Applied Analytical Photonics Group (Dr.RolandHass) at the University of Potsdam, where she acts as asenior scientist and focuses her research on the investigation of crystallization processes in highly concentrated
suspensions.