TOA (C24H51N), a tertiary amine, is a colorless liquid with a minimum assay of 98% ( molecular weight of 353.67 g/mol and a density of 0.809 g/cm 3 ). Succinic acid (99.5%) (Himedia Laboratories Pvt. Ltd. India) is a dicarboxylic acid. The diluents such as Benzyl alcohol (Spectrochem Pvt. Ltd. Mumbai, India), 1-Decanol (Himedia Laboratories Pvt. Ltd., India), and 2-Octanol (Tokyo Chemicals Industry Co. Ltd, Japan) are of the analytical grade and were used without further purification. To prepare the different concentrations of succinic acid distilled water was used. NaOH used for the titration was supplied by Merck Specialities Pvt. Ltd, India and is of analytical grade. Oxalic acid (99.8%) was used for the standardization of the NaOH and supplied by Merck Pvt. Ltd., India. Phenolphthalein solution (pH range 8.2 to 10.0) was used as an indicator for titration and was obtained from Merck Pvt. Ltd., India. The initial concentration of succinic acid was varied from 0.14mol/kg to 0.5mol/kg to obtain the equilibrium data. TOA was used at 0.57mol/kg as a basis of active diluents in the reactive extraction. Physical extraction was also done by using these diluents. TOA concentration was varied from 0.11mol/kg to 0.57mol/kg by keeping succinic acid concentration constant at 0.5mol/kg.