Spectrophotometric determination of iron(Ⅲ) by extraction of its chinoform complex with molten naphthalene

A method of liquid-liquid extraction of iron(Ⅲ) chinoform complex with molten naphthalene followed by solid-liquid separation was successfully applied to the determination of the trace amounts of iron(Ⅲ). The complex formed between iron(Ⅲ) and chinoform was quantitatively extracted into molten naphthalene. After extraction, the solidified crystals of the complex and naphthalene were dissolved in DMF, and the absorbance of the solution was measured at 480 or 620 nm against the reagent blank. The amounts of iron(Ⅲ) were calculated from the calibration. The method was compared with the chloroform method