Tag Archives: nucleation

HANBAT International Workshop on Industrial and Pharmaceutical Crystallization

Crystallization is a complicated process where the final crystal product is a function of thermodynamics as well as kinetic and physical phenomenon. Continue reading

19th International Workshop on Industrial Crystallization – BIWIC 2012

During BIWIC 2012 (19th International Workshop on Industrial Crystallization) in China, I will present a poster – Amalgamated Sugar Experiences with Inline Particle Size, Shape, and Count Characterization:  Real-Time Crystal Nucleation and Growth Rates in an Industrial Semi-batch Crystallizer. Continue reading

How To Optimize Crystal Size Distribution, Improve Filtration Rates, and Batch Consistency

httpv://www.youtube.com/watch?v=5VeCg6LQSYY

Chemists and Engineers need to quickly develop repeatable crystallization processes with fast cycle times. Continue reading

Designing Effective and Efficient Crystallization Processes

This is the sixth blog post in a special series dedicated to crystallization.  In case you missed the previous posts in the series, they are available here:

Previously, we looked at a case study that neatly illustrated the concept that slow supersaturation generation often results in a growth dominated process that is typically repeatable. As a rule of thumb, slow cooling works great – but its main drawback is the extended cycle times that often result. To overcome this problem, a common technique often used is non-linear cooling.

If we dive a little bit deeper into the governing equations of crystal growth and nucleation.. Continue reading

Crystallization Processes in Polymer-Based Materials – Call For Papers

While browsing through the LinkedIn Crystallization Community yesterday, I noticed a discussion started by Mircea Chipara indicating that the Journal of Materials Science is accepting contributions on the topic of Crystallization Processes in Polymer-Based Materials. Continue reading

Supersaturation: Driving Force For Crystal Nucleation & Growth

This is the third blog post in a series dedicated to crystallization.  In case you missed the first and second in the series, they are available here: Introduction to Crystallization and Precipitation and Common Ways to Reduce Solubility and Drive Crystallization.

Supersaturation is the driving force for all solution crystallization processes. Crystallization scientists gain control over crystallization process and product quality by carefully controlling the prevailing level of supersaturation during the process. Continue reading

Crystallization control: measuring supersaturation with ReactIR, or measuring crystal nucleation and growth with FBRM

Crystallization-control-FBRM-EasyMax-crystallizer-METTLER-TOLEDO

Crystallization control

A question was posted regarding crystallization monitoring and control:

“If you had to choose between supersaturation control or FBRM crystal size control on an industrial scale, which would you choose?”

Supersaturation monitoring and control only makes sense if you have a very reliable model of the system (i.e. where you can predict nucleation and growth as a function of supersaturation), stable reactor control, and a precise supersaturation measurement.

In R&D this is certainly achievable, and there are good examples of supersaturation control including this on-demand webinar, by Dr. Mark Barrett, describing calibration-free supersaturation control.

However, in an industrial crystallizer, your supersaturation-based control would likely be based on limiting the level of supersaturation to avoid conditions that would produce high levels of spontaneous or secondary nucleation.

And that’s not really control, just avoidance.

Continue reading