Separation and preconcentration of Mn-VII/Mn-II speciation on crosslinked chitosan and determination by flame atomic absorption spectrometry

A novel method for the separation and preconcentration of Mn-VII/Mn-II with crosslinked chitosan (CCTS) and determination by flame atomic absorption s pectrometry (FAAS) has been developed. The adsorption rate of CCTS for Mn-V II was 98% at pH 3, while Mn-II was not adsorbed. Mn-VII was eluted from th e CCTS with 10% (m/v) oxammonium hydrochloride and determined by FAAS. Mn-I I was determined from the total manganese present after Mn-II in the water samples was transformed into Mn-VII. The detection limit (3 sigma, n = 10) for Mn-VII was 1.98 mug l(-1) and the relative standard deviation less than 6.6% at the 10 mug l(-1) level. The method was applied to environmental wa ter samples with recoveries of between 95-103%.