Thermochimica Acta, Vol.644, 13-19, 2016
Solid-liquid equilibria of indole binary systems
Solid-liquid equilibrium temperatures, obtained using a differential scanning calorimetry (DSC) tech-nique, are reported for indole(1)+n-C-20(2), or +n-C-24(2) or +n-C-50(2) systems. Values of the eutectic heat and of the heat of melting needed to determine the final composition of the eutectic points on the basis of the Tamman plots are also given. At chi(1) > chi(1eu), (eutectic mole fraction), the mixtures with n-C-20, or n-C-24 show positive deviations from the Raoultis law, which reveal the existence of indole-indole interactions in that range of concentration. At chi(1) < chi(1eu), the systems show an ideal behaviour. The mixture with n-C-50 is characterized by negative deviations from the Raoult's law due to the very different size of the mixture components. Systems formed by indole and n-alkane, aromatic compound or alkyl-naphthalene have been investigated by means of the DISQUAC model. The interaction parameters for the aliphatic/amine contacts in the studied mixtures are reported. DISQUAC improves results from the ideal solubility model. (C) 2016 Elsevier B.V. All rights reserved.