VLE and LLE in ternary systems of two associating components (water, aniline, and cyclohexylamine) and a hydrocarbon (cyclohexane or methylcyclohexane)

• LLE and VLE in ternary systems of amines, water, and cyclic hydrocarbon were measured.
• Interaction parameters were fitted for the binary subsystems.
• Phase equilibria were predicted by means of UNIQUAC, NRTL, ESD EOS, and mod. UNIFAC (Do).
• The water + CH + CHA and water + MCH + CHA systems show unusual liquid phase behaviour.
• The VLE could be predicted successfully in most cases.

The isothermal vapour–liquid equilibria (VLE) of the five ternary mixtures water + cyclohexane + aniline (A), water + cyclohexane + cyclohexylamine (B), water + methylcyclohexane + aniline (D), water + methylcyclohexane + cyclohexylamine (E), and methylcyclohexane + aniline + CHA (F) with industrial relevance were determined at temperatures between 333.15 K and 363.15 K at reduced pressures. Additionally, the liquid–liquid equilibria (LLE) of the four ternary systems (B), (D), (E), and cyclohexane + aniline + cyclohexylamine (C) were determined at temperatures between 298.15 K and 333.15 K at atmospheric pressure. In total, 185 LLE and 121 VLE measurement points are presented and discussed.The experimental results were compared with the predictions of the activity coefficient models UNIQUAC and NRTL, and of the equation of state proposed by Elliott, Suresh, and Donohue (ESD EOS) based on binary interaction parameters. In order to estimate the binary parameters required for calculation, the VLE of the binary cyclohexane + aniline (G) system was measured at 333.15 K and 353.15 K at reduced pressures. Furthermore, the prediction results of the group contribution method modified UNIFAC (Dortmund) are included. Interaction parameters of new amine group at cycloaliphatic hydrocarbon have been used in the calculation.

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