Extraction Equilibria of Gibberellic Acid by Tridodecylamine Dissolved in Alcohols

Gibberellic acid (1.877.10(-3) mol.kg(-1)) extraction from aqueous solution using tridodecylamine (TDA, 0.1 mol.kg(-1) to 0.8 mol.kg(-1)) as extractant dissolved in three solvents (isoamyl alcohol, octane-1-ol, and decane-1-ol) at 298 K has been studied. Extraction parameters such as loading factor Z, extraction efficiency E, and distribution coefficient D, have been found using experimental data. The highest removal of gibberellic acid is found to be 96.37 % (D = 26.602, TDA = 0.5 mol.kg(-1)) with isoamylalcohol, 87.74 % (D = 7.160, TDA = 0.4 mol.kg1) with octane(-1)-ol, and 71.87 % (D = 2.554, TDA = 0.4 mol.kg1) with decane(-1)-ol. As per the experimental values of Z (1.19 to 6.52 with isoamyl alcohol, 0.85 to 5.26 with octane(-1)-ol, and 0.71 to 4.18 with decane(-1)-ol) and Bizek approach, the equilibrium complexation constants for 1:1 and 1:2 acidTDA complexes have been determined. The linear solvation energy relationship (LSER) model is used to represent the extraction equilibrium of acid by TDA. D values are predicted using the LSER model parameters which fit the experimental results.