Equilibrium of two liquid phases and critical phenomena in a ternary system of cyclohexane-pyridine-acetic acid in the 10–55°C range

A visual polythermal method is used to study the mutual solubility of components and critical phenomena in a ternary system of cyclohexane-pyridine-acetic acid in the 10.0–55.0°C range. It is noted that the isothermal solubility diagrams of the system in the 10.0–52.5°C range is characterized by the occurrence of a closed separation region. A temperature dependence of the mixture composition, which corresponds to the critical point of solubility, is determined. It is found that with the increase in the temperature a two-liquid phase region disappears through a non-critical point.