Abstract
The extraction of Fe(III) with Bis(2,4,4-trimethylpentyl) phosphinic acid, commonly known as CYANEX 272, in kerosene from aqueous sulphate medium was investigated. The extraction was found to increase with extractant and Fe(III) concentration while it decreases with hydrogen ion and sulphate concentration in the aqueous phase. The stoichiometry of the extracted metal species was found to be Fe(HSO4) A2.2(H2A2). The equilibrium constant and thermodynamic functions of Fe(III) extraction were calculated. Stripping investigations indicated that H2SO4 of concentration (0.5-5 M) is effective for stripping Fe(III). The experimental obtained capacity of CYANEX 272 was found to be 0. 2 M Fe(III) per mole extractant after four stages. Results of the effect of temperature indicate that the Fe(III) extraction in the investigated system is endothermic.