Study On Determination Of Arsenic And Mercury In Drinking Water Source By Atomic Fluorescence Spectrometry

Because the background values of mercury and arsenic in natural water are very low,such as the Yangtze River drinking water source is fluidity,generally mercury below 0.001 ug/L,arsenic below 0.1 ug/L.This requires higher requirements when atomic fluorescence spectrometer is used for testing.At present,the detection limits of arsenic and mercury are 0.01 ug/L and 0.001 ug/L respectively,but the effect of arsenic on the fluorescence method is very large,so in the determination of arsenic concentration,interference factors have a greater impact on the detection results,the detection limit of mercury is higher than the actual content of water samples.Through exploring the detection method of Trace Arsenic and mercury in drinking water source by atomic fluorescence spectrometer,we can provide a more reliable basis for large-scale detection of arsenic and mercury in water quality.In this paper,the atomic fluorescence spectrometry of arsenic is carried out to optimize the parameters of the instrument,so that the results of the determination can fully meet the performance indicators of the instrument and relevant specifications,and a set of reasonable operating procedures can be found to reduce the detection error as far as possible in the daily detection,so that the entire detection process can be completed scientifically.Further,the working parameters of the instrument were optimized by atomic fluorescence spectrometry.Solid phase extraction(SPE)combined with modified resin was used to enrich and elute mercury.The results showed that the concentration and elution efficiency of mercury in water exceeded 5.0ng/L and reached 74-82%.When the content of mercury exceeded 10.0ng/L,the efficiency was about 80%.It tends to be stable and has high repeatability,which basically meets the requirements of water quality detection for drinking water sources in the Yangtze River.As a comparison,the trace mercury attachment tried to enrich and separate.In the experiment,the sample amount was adjusted to 4 mL,the detection limit was 0.0002 ug/L,the sensitivity was reduced by an order of magnitude,the recovery was over 90%,and the concentration of mercury above 20.0 ng/L could be satisfied.It was the atomic fluorescence spectrometry method for the determination of ultra-trace mercury in water samples.Another method of separation and enrichment.Compared with SPE,this method has the advantages of low cost,high dependence on instruments and high maintenance rate of Trace Mercury accessories.A large number of experimental results show that the optimization of measurement conditions plays a key role in the determination of arsenic and mercury by atomic fluorescence spectrometry(AFS)because of its high sensitivity,accuracy,precision and good reproducibility.Moreover,the enrichment method of mercury can be further improved.Combined with SPE,the use of enrichment materials can reduce the cost of use at the same time.Meet test specification requirements.Industrial production in practical work has great value of popularization and application,and provides a good preconcentration and separation method for the enrichment and separation of mercury.