Micelle-mediated extraction for direct spectrophotometric determination of trace uranium(VI) in water samples

The possibility of using Dibenzoylmethane (DBM) for uranium(VI) concentrating by the way of micellar extraction at cloud point temperature and later spectrophotometric determination was investigated. Under the optimum conditions, preconcentration of 50 mL of water samples in the presence of 0.2% (w/v) octylphenoxypolyethoxy ethanol (Triton X-114), 2 x 10(-4) mol L-1 DBM and 2 x 10(-3) mol L-1 buffer solution (pH=9) gave a limit of detection 11 ng mL(-1) , and the calibration graph was linear in the range of 15-300 ng mL(-1) . The recovery under optimum working conditions was higher than 98%. The proposed method has been applied to the spectrophotometric determination of uranium(VI) in natural water samples after cloud point extraction with satisfactory results.