Determination of Hg in Water-Purifying Agents with DMA80 Direct Mercury Analyzer

The DMA80 direct mercury analyzer was applied to the determination of trace amount of mercury in water-purifying agents.Analytical parameters of the instrument,including drying temperature,drying time,decomposition temperature,decomposition time,waiting time and amalgamating time were studied and optimized.Linear relationships between values of fluorescence intensity and mass faction of mercury were kept in 2 ranges,i.e.one within 300 μg·L-1 and the other between 300-5 000 μg·L-1,with values of detection limit (3s) of 0.029 ng and lower limit of determination (10s) of 0.095 ng.The proposed method was applied to the analysis of substantial samples,giving values of recovery and RSD (n=6) in the ranges of 90%-100% and 0.8%-1.1%,respectively.