A Ghanadzadeh - Department of Chemistry, Faculty of Science, University of Guilan, Rasht, Iran
S.L Seyed Saadat - Department of chemistry, University of Guilan , 41335 Rasht ,Iran
S Hosseinzadeh - Department of Chemistry, Faculty of Science, University of Guilan, Rasht, Iran

In this research, experimental solubility and liquid-liquid equilibrium (LLE) data for (water +propionic acid + active amyl alcohol) ternary system were obtained at T = 298.2K and p =101.3kPa for the first time. LLE data for extraction of organic acids from water are importantin evaluation of industrial extraction processes. The precise LLE data are always needed forefficient separation operations, which can be obtained from direct measurements. Theconsistency of the experimental tie-line data was determined through the Othmer–Tobias andHand correlation equations for the system. The experimental tie-line data were comparedwith those calculated by the UNIQUAC and NRTL models [1-4].