抄録
A very simple and sensitive method for the extraction-spectrophotometric determination of antimony(V) and (III) was developed. It was found that antimony(V) reacts with 2-hydroxyisocaproic acid in weak acidic aqueous solution on heating for 15min at 45°C and that the complex anion formed can be extracted into chlorobenzene with Malachite Green. Antimony(III) reacts quickly irrespective of the temperature. However, the Sb(III)-complex anion formed can not be extracted in the presence of citrate, whereas Sb(V)-complex anion can be extracted and determined under the same condition. This significant difference in reactivity between citrate and these two species was applied to the differential determination of antimony(III) and antimony(V). The calibration graph was linear over the range 0.19-11.5μg for antimony(V), and 0.15-8.1μg for antimony(III).
