The phase behaviour of three (1-decanol + n-dodecane)-mixtures in the presence of supercritical CO2 was investigated. Phase equilibrium measurements were conducted at temperatures ranging between 308K and 348K, with solute mass fractions ranging between 0.017 and 0.621. The experimental data emphasize the dominant influence of n-dodecane in the solute mixture. It has been proposed that the presence of n-dodecane interrupts the formation of alcohol multimers and thus significantly improves the solubility of 1-decanol in supercritical CO2. The ternary system also displays a slight cosolvency effect. The experimental data was used to determine solute solute binary interaction parameters for the RK-Aspen model in Aspen Plus (R). Addition of these interaction parameters improved the correlative capability of the equation of state allowing for future improved process modelling of systems involving these components. (C) 2015 Elsevier B.V. All rights reserved.