Measurements of activity coefficients at infinite dilution in vegetable oils and capric acid using the dilutor technique

Author(s)

Belting, Patricia C. ^{[1, 2]} ; Rarey, Jurgen ^[2] ; Gmehling, Jurgen ^[2] ; Ceriani, Roberta ^[3] ; Chiavone-Filho, Osvaldo ^[4] ; Meirelles, Antonio J. A. ^[1]

Affiliation

^[1] Univ Estadual Campinas, Fac Food Engn, Dept Food Engn, BR-13083862 Campinas, SP - Brazil

^[2] Carl von Ossietzky Univ Oldenburg, Tech Chem FK V, D-26111 Oldenburg - Germany

^[3] Univ Estadual Campinas, Fac Chem Engn, BR-13083852 Campinas, SP - Brazil

^[4] Univ Fed Rio Grande do Norte, Dept Chem Engn, BR-59066800 Natal RN - Brazil

• Document type: Journal article
• Source: Fluid Phase Equilibria; v. 361, p. 215-222, JAN 15 2014.
• Web of Science Citations: 6

Abstract

This paper reports experimental activity coefficients at infinite dilution, gamma(not similar to)(i), for methanol, ethanol and n-hexane in three refined vegetable oils (soybean, sunflower, and rapeseed oils) measured using the dilutor technique (inert gas stripping method). The measurements were carried out in the temperature range between 313.15 and 353.15 K. Furthermore, activity coefficients at infinite dilution for various solutes (acetone, methanol, ethanol, n-hexane, cyclohexane and toluene) were measured in capric (decanoic) acid using the same technique in the temperature range from 313.13 to 353.30 K. The new data obtained for capric acid and soybean oil were compared with already published experimental data. Additionally, densities of the investigated vegetable oils were measured in the temperature range from 293.15 to 353.15K. Using the experimental gamma(not similar to)(i) values obtained over the temperature range, the partial molar excess Gibbs energy (Delta G(i)(E,not similar to)), enthalpy (Delta H-i(E,not similar to)) and entropy (Delta S-i(E,not similar to)) at infinite dilution were determined. The relative error for the gamma(not similar to)(i) measurements carried out using the dilutor technique is approximately +/- 2.5%. The measured gamma(not similar to)(i) data in the investigated refined vegetable oils were also compared with the results of the group contribution methods original UNIFAC and modified UNIFAC (Dortmund) and an extension of the latter method to triacylglycerols was proposed. (C) 2013 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 10/16634-0 - Separation processes by stripping in the fat and oil industry
• Grantee: Roberta Ceriani
• Support Opportunities: Regular Research Grants
• FAPESP's process: 09/54137-1 - Acquisition of a particle size/distribution analyzer, a zeta potential measurement system, a spray dryer, and an ultra-high-pressure liquid chromatograph/mass spectrometer
• Grantee: Miriam Dupas Hubinger
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 08/56258-8 - Phase equilibrium and purification processes in the production of biofuels and biocompounds
• Grantee: Antonio José de Almeida Meirelles
• Support Opportunities: Program for Research on Bioenergy (BIOEN) - Thematic Grants