Picture of UK Houses of Parliament

Leading national thinking on politics, government & public policy through Open Access research

Strathprints makes available scholarly Open Access content by researchers in the School of Government & Public Policy, based within the Faculty of Humanities & Social Sciences.

Research here is 1st in Scotland for research intensity and spans a wide range of domains. The Department of Politics demonstrates expertise in understanding parties, elections and public opinion, with additional emphases on political economy, institutions and international relations. This international angle is reflected in the European Policies Research Centre (EPRC) which conducts comparative research on public policy. Meanwhile, the Centre for Energy Policy provides independent expertise on energy, working across multidisciplinary groups to shape policy for a low carbon economy.

Explore the Open Access research of the School of Government & Public Policy. Or explore all of Strathclyde's Open Access research...

Establishment of a continuous sonocrystallization process for lactose in an oscillatory baffled crystallizer

Siddique, Humera and Brown, Cameron J. and Houson, Ian and Florence, Alastair J. (2015) Establishment of a continuous sonocrystallization process for lactose in an oscillatory baffled crystallizer. Organic Process Research and Development, 19 (12). pp. 1871-1881. ISSN 1083-6160

Text (Siddique-etal-OPRD-2015-Establishment-of-a-continuous-sonocrystallization-process-for-lactose-in-an-oscillatory)
Accepted Author Manuscript

Download (4MB)| Preview


    Crystallization at production scale (>10 kg) is typically a poorly understood unit operation with limited application of first-principles understanding of crystallization to routine design, optimization, and control. In this study, a systematic approach has been established to transfer an existing batch process enabling the implementation of a continuous process in an oscillatory baffled crystallizer (OBC) using ultrasound. Process analytical technology (PAT) was used to understand and monitor the process. Kinetic and thermodynamic parameters have been investigated for lactose sonocrystallization using focused beam reflectance measurement (FBRM) (Mettler Toledo) and mid-infrared spectroscopy (mid-IR) (ABB) in a multiorifice batch oscillatory baffled crystallizer (Batch-OBC). This platform provides an ideal mimic of the mixing, hydrodynamics and operating conditions of the continuous oscillatory flow crystallizer (COBC) while requiring only limited material. Full characterization of the hydrodynamics of the COBC was carried out to identify conditions that deliver plug-flow behavior with residence times of 1–5 h. The results show that continuous crystallization offers significant advantages in terms of process outcomes and operability, including particle size distribution (mean particle size <1500 μm) of alpha lactose monohydrate (ALM), as well as reduced cycle time (4 h compared to the 13–20 h in a batch process). Continuous sonocrystallization was performed for the first time at a throughput of 356 g·h–1 for 12–16 h. During the run at near plug flow, with supersaturation and controlled nucleation using sonication, no issues with fouling or agglomeration were observed. This approach has demonstrated the capability to provide close control of particle attributes at an industrially relevant scale.