Determination of manganese in mater samples by flame atomic absorption spectrometry after cloud point extraction

Cloud point extraction has been used for the preconcentration of manganese, after the formation of a complex with 1-(2-thiazolylazo)-2-naphthol (TAN), and later analysis by flame atomic absorption spectrometry using octylphen oxypolyethoxyethanol (Triton X-114) as surfactant. The chemical variables a ffecting the separation phase and the viscosity affecting the detection pro cess were optimized. Under the optimum conditions (i.e., pH = 9.2. [TAN] = 2.0 X 10(-5) mol l(-1), [Triton X-114] = 0.05%, added methanol volume = 0.2 ml), preconcentration of 50 ml of sample solution permitted the detection of 0.28 ppb for manganese. The enhancement factor was 57.6. The proposed me thod has been applied to the determination of manganese in water samples.