Reaction products of ferrous ions with O-phennthroline and fluorescein derivative and some analytical applications

ABSTRACT

The reaction between the ferrous metal ions, o-phenanthroline, neocuproine, bathophenanthroline as primary ligands [L1] and fluorescein [FlCOOH], 2',7'-dichlorofluorescein [Cl2FlCOOH] and 4',5'-dibromofluorescein [Br2FlCOOH] as secondary ligands were investigated. Orange colored ternary complexes are formed between the ferrous metal ions and the ligands. The chemical formula [M[L1]2]2+[Br2FlCOO-]- and [M[Ll]2]2+[Cl2FlCOO-]- were proposed for the reaction product between the coordinated metals and the secondary. The absorbance characteristics of the formed ternary complexes were determined. The interferences of the ions with the determination of Fe[III], Co[II] and Ni[II] in the same alloys, e.g. the nimonic series, ferrochrome, iron-mining fields and in freshwater were investigated. Simple, rapid and inexpensive methods for the spectrophotometric microdetermination of the studied metals were proposed and the methods were successfully applied in analysis of samples. The developed methods are most suitable in laboratories where the expensive instruments are unavailable