The (liquid + liquid) equilibria of a ternary system (water + dodecane + propylene glycol n-propyl ether) were measured at T = (288.15, 298.15, and 308.15) K under atmospheric pressure. At T = 298.15 K, the system exhibits one three-liquid-phase-coexisting tie triangle and three two-liquid-phase-coexisting envelopes in the triangle phase diagram. There is only one two-liquid-phase-coexisting envelope in the triangle phase diagram at T = (288.15 and 308.15) K. The experimental data were further correlated with the NRTL model. (C) 2011 Elsevier Ltd. All rights reserved.