Effect of initial dextrose concentration, seeding and cooling profile on the crystallization of dextrose monohydrate

A batch seeded cooling crystallizer was used to study dextrose monohydrate crystallization. Experiments were conducted to investigate how a 2% increase in the initial dextrose concentration (from 65.5 to 67.5%) would influence final crystal yield and size. The crystallizations were performed for three different seed masses and cooling profiles, consequently the influence of these parameters was also investigated. The parameters were varied in accordance with an industrial scale process. An in-line focused beam reflectance measurement probe and an in-line process refractometer were used to continuously monitor the crystallizations. The experimental results showed that the 2% increase in initial dextrose concentration had a major influence on the rate of crystallization and yield over a 24 h crystallization period, and only a minor influence on the median crystal size.

► Crystallizations were conducted at initial dextrose concentrations of 65.5 and 67.5%.
► In-line FBRM and refractometer probes were used to monitor crystallizations.
► 2% increase in initial concentration had a major influence on crystallization rate and yield.
► The 2% increase had only a minor influence on the median crystal size.
► Both seed mass and cooling profile influenced crystallization rate.