Extraction of iron(III) with a new and indigenously prepared solvent tri-iso-amyl phosphate (TAP)

A new solvent, tri-isoamyl phosphate (TAP), prepared indigenously from a by-product fusel oil of the Indian alcohol industry, has been utilised for the extraction of iron(III) from perchloric acid solutions in presence of Cl− and Br−. The optimum conditions for the extraction of iron(III) with 22% TAP in carbon tetrachloride are 6.0 M HClO4 and 0.4 M. The effect of various factors such as [H3O+], [X−] and [Fe3+] on the extraction system has been investigated. The presence of two main species in the organic layer, viz. trisolvated FeCl3 and disolvated FeCl4−, has been established. The former is predominant at lower acid concentrations and the latter at [H3O+] ⩾ 5.7 M.