Reactive extraction of gallic acid using tri-n-octylamine in a biocompatible mixture of diluents

Abstract

The present study is an approach to develop a biocompatible extraction system using tri-n-octylamine (TOA), with a modifier, 1-decanol and inert diluent, n-dodecane for the recovery of gallic acid (GA) from aqueous solution. The effects of GA concentration, modifier volume ratio, solvent polarity and pH of aqueous solution on reactive extraction of GA, are examined. With optimized extraction system of 20% TOA with 40% 1-decanol and 40% n-dodecane, further investigations are carried out for the determination of reaction stoichiometry ( m = 1.53 – 2.02), equilibrium constants (K E = 20.30 – 83.23) and thermodynamics (∆H o = -94,385.86 J.mol –1 , ∆S o = -267.51 J.mol –1 .K –1 and ∆G o = -14,627.83 to -6602.54 J.mol –1 .K –1 ) in the range of GA concentrations (0.00294 kmol.m –3 – 0.04703 kmol.m –3 ) at different temperature (298.15 K – 328.15 K) using a bio-inspired, population based genetic algorithm, differential evolution (DE). At the temperature 298.15 K, maximum distribution of GA in organic phase is found as 81%.