Spectrophotometric determination of bismuth (III) via pyrocatecol violet dye as chromogenic reagent

Abstract

Direct, rapid, simple, precise and an accurate spectrophotometric method for the estimation of bismuth (III) ion was proposed. The reaction of bismuth (III) ion with pyrocatecol violet in aqueous solution in the presence of cetyl trimethyl ammonium bromide) CTAB)to form at pH 3.4 a colored complex which was showing maximum absorption at 648 nm. The linearity of the proposed method was obeyed Beer's law over the concentration range of 5-200 µg /25 ml i.e (0.2-8.0) ppm. The molar absorptivity factor found to be 1.72×104 l/mol.cm and, Sandall's sensitivity index was 0.01215 µg/cm. The proposed method was successfully applied for the determination of bismuth (III) in water and pharmaceutical preperation (Tablet).