Prediction of water activity in sugar solutions using models of group contribution and equation of state

Citation
Ce. Velezmoro et al., Prediction of water activity in sugar solutions using models of group contribution and equation of state, J CHEM EN J, 33(4), 2000, pp. 645-653
Citations number
35
Categorie Soggetti
Chemical Engineering
Journal title
JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
ISSN journal
00219592 → ACNP
Volume
33
Issue
4
Year of publication
2000
Pages
645 - 653
Database
ISI
SICI code
0021-9592(200008)33:4<645:POWAIS>2.0.ZU;2-6
Abstract
Data of water activity in sugar solutions (of sucrose, glucose, fructose, a nd maltose) were obtained experimentally utilizing a dew point device (Aqua -Lab CX-2) at temperatures of 25, 30, and 35 degrees C, and atmospheric pre ssure. The thermodynamic models of group contribution (UNIFAC, ASOG) and of equations of state (EOS PR/Classic; EOS PR/SV) were used for modeling and predicting water activity in these solutions. A single set of parameters wa s obtained for the temperatures tested by fitting the UNIFAC and ASOG model s to the experimental data; equations of state were used to determine binar y interaction parameters for water-sucrose, water-glucose, water-fructose, and water-maltose. Water activity was predicted for a quaternary mixture (s ucrose, glucose, fructose and water), with average relative deviations of 0 .5% and 1.3% for the EOS PR/SV and EOS PR/Classic, respectively. For the gr oup contribution methods, the deviations were 0.48% for the ASOG and 0.52% for the UNIFAC.