Study of lactose crystallization in water-acetone solutions

This paper describes a study on the process of lactose crystallization using a water-acetone solution. The selection of lactose was based on its significance for the pharmaceutical and food industries and on the fact that the crystallization of this organic compound has been little studied and is, unlike inorganic compounds, complex. The objective was to achieve lactose batch crystallization of solutions by analyzing the crystal growth under different operating conditions. To determine solubility curves, the experiments were carried out based on gravimetric methods. All the crystallization experiments were performed according to the methodology proposed by Nyvlt in 1985, who uses the temperature at which the first crystals appear (nucleation) to establish the width of the metastable zone and the induction time. The results showed that crystals with different average diameters, shape factors, and recovered mass were obtained for different water-acetone compositions. (C) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.