An Equilibrium Phase Diagram for the Glucose-Cellobiose-Water System at 30.5 °C

The solid-liquid equilibrium phase diagram for the ternary system of water-glucose-celloblose was studied at 30.5 °C. Samples of known composition were equilibrated at 30.5 °C over a period of 7 days. The resultant saturated liquid phase as well as a wet sample of the solid phase were analyzed by high-pressure liquid chromatography. Both graphical analysis as well as optical microscopy were used to Identify the solid phases. The compositions of the saturated liquid phase and the Identities of the accompanying solid phases are reported. Glucose monohydrate and anhydrous celloblose were Identified as the solid phases. For the three-phase region, the composition of the liquid at the Invariant point was calculated to be 50.1 wt % glucose, 5.0 wt % celloblose, and the remainder water. The two-phase region of solid anhydrous celloblose and saturated liquid was found to dominate the ternary diagram. This suggests that it is possible to obtain celloblose in sufficient purity and yield from aqueous solutions obtained by the enzymatic hydrolysis of cellulose. © 1980, American Chemical Society. All rights reserved