Liquid−Liquid Equilibria of Acetic, Propionic, Butyric, and Valeric Acids with Trioctylamine as Extractant

Liquid−liquid equilibria of aqueous solutions of acetic, propionic, butyric, and valeric acids with trioctylamine in various diluents, 1-octanol, chloroform, methyl isobutyl ketone, and tetrachloromethane, were determined at 298 K. An expression of the extraction equilibrium is derived, and the apparent extraction equilibrium constants ( K 11 ) are evaluated. The predicted loading of trioctylamine agrees well with the experimental values. The relationship between the K 11 and the hydrophobicities of the acids is discussed.