Distribution equilibrium of penicillin G between water and organic solutions of Amberlite LA-2

Equilibrium studies on the distribution of penicillin G between aqueous solutions and Amberlite LA-2 (a secondary amine) in mixtures of n-butyl acetate and kerosene were made in the temperature range 288–308 K. Experiments were performed as a function of aqueous pH, penicillin G concentration in the aqueous phase, and amine concentration in the organic phase. The composition of the complex present in the organic phase and the equilibrium constant for the formation of this complex were numerically determined at different temperatures. In addition, the apparent enthalpy and entropy for complexation reaction were calculated.