Determination of trace mercury in geochemical samples by atomic fluorescence spectrometry

The analysis method of mercury in geochemical exploration samples by hydride generation-atomic fluorescence spectrometry combined with polyethylene film closed ore dissolution in concussive water bath was proposed.Parameters,including ore dissolution method,lamp current,carrier gas,shielding gas flow and potassium borohydride concentration,were optimized.Under optimal conditions the calibration curve of mercury was established,the correlation coefficients were in range of 0.999 1-0.999 3,and the detection limit of mercury was 0.125 ng/g.The proposed method was applied to the analysis of standard and actual geochemical exploration samples,and the determination results were consistent with the certified values or those obtained by two-stage gold amalgamation cold vapor atomic absorption spectrometry after closed dissolution.The relative standard deviation(RSD,n=5) was less than 3.5 %.