EXTRACTIVE SPECTROPHOTOMETRIC DETERMINATION OF IRON (II) USING AN ION ASSOCIATION COMPLEX FORMATION

Document Type : Original Article

Authors

1 Chemistry Department, Faculty of Science, Benha University, Benha

2 Analytical Chemistry Department, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt.

3 Analytical Chemistry Department, Faculty of Pharmacy, Zagazig University, Zagazig. Egypt

4 Analytical Chemistry Department, Faculty of Pharmacy, zagazig University, Zagazig, Egypt

Abstract

Spectrophotometric determination of micro amount of iron has been developed using a solvent extraction of an ion association complex of ferrous ion. The method is dependent on the formation of an ion associate complex of iron (II) with ethylene diamine disuccinic acid as a primary ligand and cetyl trimethyl ammonium bromide (CTMA) as counter ion, which is extracted into 1.2- dichloroethane (DCE). The complex is formed at pH = 5.0-7.0 and the iron concentration can be determined by measuring the absorbance directly in the organic phase. The apparent molar absorptiviy is 1.73 x 105 L mol-1 cm-1 and Sandell sensitivity is 0.32 mg cm-1, free from interferences. The proposed method was applied to the determination of iron in water, fruit juice, wine, food minerals and pharmaceutical formulations.