Acetylacetone as chelating reagent, extracting solvent, and electrolysis medium: Polarographic determination of uranium(VI) and iron(III)

The chelating reagent acetylacetone has been examined as a polarographic medium; a method for its purification has been developed and it is found that the specific conductance is 4.2 x 10(-8) mho/cm, the accessible potential ranges are from -0.16 to -2.26 V vs. Ag/0.1M AgClO(4) for the pure solvent and from -0.35 to -2.20 V in the solvent after extraction. In pure solvent ferric acetylacetonate exhibits one wave and the uranyl complex gives two waves. After extraction from aqueous solution at pH 6.8-7.0, both metal acetylacetonates are reduced more reversibly and at more positive potential than in the pure solvent. Calibration curves are linear in the range 10(-5) -10(-3)M metal ion in the extract. The direct polarographic determination of uranium and iron in acetylacetone after extraction of the chelate from aqueous solution has been developed.