Interference and Elimination of High Concentration of Cobalt on the Determination of Arsenic,Antimony and Bismuth in Hydride Generation

Interferences of high concentration of cobalt on the determination of arsenic,antimony and bismuth were studied and its elimination was investigated.The result indicated that the adding of high hydrochloride concentration and thiourea-ascorbic acid-hydroxylamine hydrochloride concentration could eliminate the interference of high concentration matrix on the determination of target analytes.Based on this,a method was proposed for the direct determination of trace arsenic,antimony and bismuth in cobalt oxide product by hydride generation-atomic fluorescence spectrometry.This method was simple,rapid and without cobalt matching or separation process.The calibration curves showed good linearity in the range of 0-100 μg/L.The detection limits of arsenic,antimony and bismuth(S/N=3) were 0.29 μg/L,0.26 μg/L and 0.24 μg/L,respectively.The RSDs for determination were in the range of 2.1%-9.8%(n=5) and the spiked recoveries of the elements ranged from 90% to 114%.