Effect of pH on the extraction characteristics of succinic and formic acids with tri-n-octylamine dissolved in 1-octanol

Abstract

A study was made on the extraction equilibria of succinic and formic acids from aqueous solutions using tri-n-octylamine (TOA) in 1-octanol. It was shown that the loading values of TOA decreased with increasing pH values. The apparent equilibrium constants for each acidamine complex were determined by an equilibrium model. In the case of succinic acid, the formation of a bisuccinate anion played an important role in the stoichiometry of the acid-amine complex.