Liquid-liquid extraction equilibrium study of vanadium(V) from nitrate medium by technical grade D2EHPA dissolved in kerosene

Abstract

The titled system was investigated as functions of aqueous pH, [V (V)] and [NO3−], and organic [D2EHPA]. The system is non-ideal as the log D value decreases with [V (V)]. Two types of mechanisms were identified through the pH dependence study; below pH 2.5, the log D value increases with increasing pH value with a limiting slope of 0.35, whereas, above pH 2.5, the limiting slope is -0.32. The extractant dependence is 0.24. The extraction ratio increases with increasing [NO3−], showing the salting out effect. Kerosene appears as a suitable diluent. The system is exothermic with ΔH =-12.34 kJ/mol. The loading capacity was 6.11 g V (V)/100 g extractant. A 0.5 mol/L H2SO4 solution appeared to be a suitable stripping agent.