Use of quercetin in an improved method for molybdenum determination in waste water, silicate rocks and diverse alloys

A simple and highly sensitive spectrophotometric method for molybdenum(VI) determination has been developed. The method is based on solubilizing the binary molybdenum-quercetin complex and sensitizing the color reaction with cetyltrimethylammonium bromide (CTAB). The optimal conditions for the quantitative determination of molybdenum are studied. In KCl-HCl buffered medium of pH 2.3, the molar absorptivity of the 1:2:2 (Moquercetin-CTAB) ternary complex is 2.03 x 105 l.mol-1.cm-1 at 420 nm. The system obeys Beer's law up to 0.30 μg/ml of molybdenum and the sensitivity index is 0.47 ng.cm-2. The method is free of interference of most of the common metal ions and anions. The developed procedure has been successfully applied to molybdenum determination in waste water, silicate rocks and diverse alloys. (authors)