Extraction of iron(III) from nitrate media with bis(2-ethylhexyl) phosphinic acid

Solvent extraction of iron(III) from nitrate media using bis(2-ethylhexyl) phosphinic acid as extractant has been proposed. A critical study of various parameters suggest that iron(III) can be quantitatively extracted in the pH range 2.0-4.5 using 0.009 M bis(2-ethylhexyl) phosphinic acid in hexane. The organic phase is stripped using 0.75 M HNO3 and iron(III) determined spectrophotometrically by thiocyanate method. The method is selective and can be applied in the presence of a large number of diverse ions. The method is found to be reproducible when applied for recovery of iron from real samples as well as its separation from other metal ions.