IC Determination of Hexavalent Chromium in Air of Working Place

IC was applied to the determination of hexavalent chromium in air of working place. Air sample of working place was collected by alkline microporous membrane filter, and the Cr(Ⅵ) on the filter was eluted ultrasonically with 4.0 mmol·L^-1 Na₂CO₃ solution. Metrosep A Supp 4-250 anionic column (250 mm×4.0 mm) was used for chromatographic separation. Mixture of 4.0 mmol·L^-1 Na₂CO₃ and 1.0 mmol·L^-1 NaHCO₃ solution was used as mobile phase, and restraining conductance detector was used in determination. Linear relationship between values of peak area and mass concentration of hexavalent chromium was kept in the range of 0.01-10.0 mg·L^-1, with detection limit (3S/N) of the method of 4×10^-3mg·L^-1. Values of recovery found by standard addition method were in the range of 95.2%-97.6%, and values of RSD's (n=6) in the range of 2.2%-3.8%.