Phase equilibria of carbohydrates:: the study of a series of glucose oligomers from glucose to maltopentaose in aqueous solution -: Experimental versus predicted data using various UNIQUAC/UNIFAC models

Vapour pressures above solutions of glucose (Glc) in water and maltose in water at both 298.06 and 317.99 K have been measured. Vapour pressures above aqueous solutions of maltotriose, maltotetraose and maltopentaose at 317.99 K have also been measured. The experimental results are compared with predictions from two existing UNIFAC type models available in the literature. Further to this a theoretical model is examined in which existing interaction parameters, calculated for the 1.2-ethanediol/water system using a molecular mechanical approach, are incorporated into the UNIQUAC equation to describe the vapour pressures of the aforementioned series of alpha-(1-4) linked Glc oligosaccharides in aqueous solution. This so-called transference principal is found to be adequate for these systems when used in conjunction with an adjustment to the coordination number used for the lattice based model. (C) 2002 Elsevier Science B.V. All rights reserved.