In this paper, the liquid-liquid equilibrium (LLE) and tie-line data of the system containing 1-butanol + water + tri-n-butyl phosphate (TBP) + ammonium chloride have been studied at 298.15, 308.15 and 318.15 K under atmospheric pressure. The influence of temperature and different concentrations of ammonium chloride have been investigated. In addition, nonrandom two-liquid (NRTL) model is applied to the system, and the relevant interaction parameters are regressed with the experimental data. The quality of the correlation is measured by the rmsd (rmsd <= 0.0131). The results show that the calculated values by NRTL model are in agreement with the determination of LLE data of the studied system in the investigated conditions. (C) 2014 Elsevier B.V. All rights reserved.