Optimal design of crystallization processes for the recovery of a slow nucleating sugar with a complex chemical equilibrium in aqueous solution: the case of lactose

DOI: 10.1021/acs.oprd.8b00323

Authors: Elena Simone (University of Leeds) , Arwen I. I. Tyler (University of Leeds) , Daniel Kuah (University of Leeds) , Xiaofan Bao (University of Leeds) , Michael Ries (University of Leeds) , Daniel Baker (University of Leeds)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Organic Process Research & Development

State: Published (Approved)
Published: January 2019
Diamond Proposal Number(s): 16566

Abstract: Lactose is the major carbohydrate in milk and, similarly to other sugars, it can exist as two anomers in solution, the α and β forms, with a ratio depending on factors including temperature and pH (mutarotation equilibrium). Lactose is extracted from whey mostly to prevent environmental pollution. In fact, the presence of this sugar can contribute to a dramatic increase in the biological oxygen demand (BOD) of whey, making its direct disposal potentially dangerous for the environment. However, preserving our ecosystem is not the only reason why lactose is recovered. Purified lactose is, in fact, a high value product, commonly used as an excipient in pharmaceutical formulations and as a carrier in dry powder inhalers. Despite the increasing interest that lactose crystallization has recently received, a full understanding of this process is still missing, particularly the link between the process parameters of the crystallization step and the properties of the final product in terms of crystalline structure, purity and particle size and shape distribution. This work is the first comprehensive study of lactose crystallization, exploring cooling and anti-solvent operations, for the determination of the effect of several operative conditions on: (i) the kinetics of nucleation, growth and agglomeration; (ii) the yield of lactose recovery from solution; (iii) the final crystal size and shape distributions; and (iv) the purity of the obtained crystals.

Journal Keywords: Lactose; crystallization; anti-solvent; anomeric purity; polymorphs

Subject Areas: Food Science, Chemistry, Biology and Bio-materials


Instruments: I22-Small angle scattering & Diffraction

Added On: 15/01/2019 09:55

Discipline Tags:

Biochemistry Chemistry Life Sciences & Biotech Food Science

Technical Tags:

Scattering Small Angle X-ray Scattering (SAXS) Wide Angle X-ray Scattering (WAXS)