COMPARISON OF EXTRACTION EQUILIBRIA OF SUCCINIC AND TARTARIC-ACIDS FROM AQUEOUS-SOLUTIONS WITH TRI-N-OCTYLAMINE

A comparative study was made on the extraction equilibria of succinic and tartaric acids from aqueous solutions with tri-n-octylamine in xyl ene. It was shown that the extractability of tartaric acid was higher than succinic acid under comparable conditions. The compositions of th e multiple-extracted complexes in the organic phase and the equilibriu m constants for the formation of the complexes were numerically determ ined. Furthermore, the mole fractions of the species present in the or ganic phase were quantitatively obtained as a function of initial conc entrations of the acids and amine. The effect of temperature on the ex traction of acids was also examined and a change of complex compositio n with temperature was seen for succinic acid in the temperature range 293-323 K. Finally, the related thermodynamic data were calculated.