A Comparative study of TOA in diluents for Reactive Extraction of Succinic Acid

Succinic acid recovery from the aqueous phase is an intrinsic downstreaming process because of its numerous applications in the pharmaceutical and food industries. Distillation, sorption, adsorption, membrane, dialysis, and electrodialysis these are the conventional methods used for acid separation. Apart from these methods, a novel technique developed called reactive extraction that delivers good selectivity and yield. Separation of succinic acid from its aqueous phase was investigated in a recent work using a tertiary amine, such as tri-n-octyl amine (TOA), with different diluents. The study based on the acid concentration ranged from 0.14 to 0.5 mol/kg, while the TOA concentration ranged from 0.11 to 0.57mol/kg to study the parameters like the distribution coefficient, loading ratio, equilibrium complexation constant, and degree of extraction. The physical extraction of succinic acid by using these three diluents was done. As compare to physical extraction, reactive extraction gives better separation efficiency. The comparison of results by using different diluents in TOA was studied. The best result was obtained at the initial concentration of acid 0.26 mol/kg and initial concentration of TOA 0.57 mol/kg in the benzyl alcohol that gives 99.44 % extraction efficiency. The order of extraction power for the diluents was found to be benzyl alcohol > 2-octanol > 1-decanol. Keywords: succinic acid; reactive extraction; distribution coefficient; degree of extraction