S.L Seyed Saadat - Department of Chemistry, Faculty of science, University of Guilan, Rasht, Iran
Sh. Asan - Department of Chemistry, Faculty of science, University of Guilan, Rasht, Iran

In this study, liquid–liquid equilibrium (LLE) data for the (water + formic acid + 1-octanol) system were experimentally obtained at T = 318.15 K and atmospheric pressure. The cloud-point titration method was used to determine solubility data. The investigated ternary system exhibits type-1 behaviour of LLE. The tie line data were determined by acidimetric titration, the Karl-Fischer technique, and refractive index measurements. The UNIQUAC and NRTL models were used to correlate the experimental tie line data. The consistency of data was determined through the Othmer-Tobias equation. Distribution coefficients and separation factors were calculated over the immiscibility region.

liquid–liquid equilibrium, Ternary system, Formic acid, NRTL, UNIQUAC