DETERMINATION OF ANTIMONY(III) AND ANTIMONY(V) IN FRESH-WATER SAMPLESBY AAS EQUIPPED WITH A QUARTZ CELL IN AN ELECTRIC FURNACE

For the determination of total antimony, the operating conditions of a hydride generation system were investigated. The total antimony was d etermined by 2 M hydrochloric acid and a 1% (w/v) sodium tetrahydrobor ate solution in a 0.125 M sodium hydroxide solution after adding potas sium iodide and cone, hydrochloric acid to a sample solution {ultimate ly: 5% (w/v) KI, 0.60 M HCl} and standing it for 15 min. The detection limit and precision of the method was 0.07 ppb (3 sigma) and +/-2.3%, respectively. For a differential determination between antimony(III) and antimony(V), the concentration of acidic solution was investigated . By using a 0.10 M hydrochloric acid solution, antimony(V) was separa ted from antimony(V). The detection limit and precision of a different ial determination was 0.19 ppb(3 sigma) and +/- 3.1%, respectively. Th e antimony(V) was determined by subtracting the concentration of antim ony(III) from that of total antimony. The method was applied to the de termination of antimony(III) and antimony(V) in a river-water sample a nd ground water samples from mines. Although antimony(III) was not det ected in the samples, antimony(V) was detected in the range of 5.53 si milar to 6.00 ppb in the mine ground-water samples.