Volume 92, №4
INVESTIGATION OF THE INFLUENCE OF HYDRATION ON THE HEAT OF EVAPORATION OF WATER FROM SUCROSE SOLUTIONS
An analysis has been made of the literature data on sucrose hydration. A platform of the most reliable experimental data has been selected. In a differential evaporation microcalorimeter, the specifi c heat of evaporation of water was measured in the process of continuous dehydration of a solution with an initial content of sucrose of 12.5 wt.%. Curves of the reduced specifi c evaporation heat versus the concentration of the solution at 40, 60, and 80o C were obtained. The infl uence of the degree of hydration of sucrose on the specifi c evaporation heat was determined. It has been shown that in the interval from the initial concentration of the solution, with degree of hydration of sucrose N = 20, to a content of sucrose of ~65 wt.% (N ~ 6), the specifi c evaporation heat grows from a value that is similar to the evaporation heat of pure water to values 3 to 4% higher than it. The most signifi cant growth in the specifi c evaporation heat (7–10%) was recorded on removing water bonded to hydroxyl groups of sucrose in the equatorial position at N ≤ 6. The concept of strongly and weakly bound hydrate water in sucrose solutions is substantiated.
Author: V. A. Mikhailik, N. V. Dmitrenko, and Yu. F. Snezhkin
Keywords: differential scanning calorimetry, evaporation calorimetry, sucrose, hydration, free and hydrate water, evaporation heat
Page: 916
V. A. Mikhailik, N. V. Dmitrenko, and Yu. F. Snezhkin .
INVESTIGATION OF THE INFLUENCE OF HYDRATION ON THE HEAT OF EVAPORATION OF WATER FROM SUCROSE SOLUTIONS //Journal of engineering physics and thermophysics.
. Volume 92, №4. P. 916.
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