Spectrophotometric Titration of Iron Using Eriochrome Blue Black R and Cetyltrimethylammonium Bromide

Abstract The ternary interaction of eriochrome blue black R (EBBR) with cetyltrimethylammonium bromide (CTAB) was investigated. Cetyltrimethylammonium bromide micelle provides complexation between Fe and EBBR with a catalytic field so as to sensitize the complexation. The aggregation of EBBR on CTAB is in accord with the Langmuir adsorption isotherm. The ternary interaction was characterized at pH 6.5 by the spectral correction technique and the Langmuir adsorption isotherm and the aggregate Fe · EBBR6CTAB78 was formed. The reaction was applied to the sensitive determination of Fe traces in samples with satisfactory results. Keywords: Cetyltrimethylammonium bromideEriochrome blue black RSpectral correction techniqueLangmuir adsorption isotherm, Determination of iron Acknowledgment Financial support from both the National High Technology Research and Development Program of China (863 Program, No. 2002AA601320) and the National Natural Science Foundation of China (50008011) is gratefully acknowledged.