Determination of total selenium in water by constant temperature REDOX reaction-hydride atomic fluorescence method
Objective To develop a simple and accurate method to determine the total selenium in water by hydride atom-ic fluorescence spectrometry so as to provide a reference for achieving a standardized operational procedure for sample di-gestion.Methods In the process of performing constant temperature oxidation-reduction reaction hydride atomic fluo-rescence spectrometry,10.00 mL of water sample was taken into a conical tube,and a polypropylene conical tube was used.Nitric acid was added to the water sample,selenium was dissolved in water at 110 C for 15 minutes,reducing agents hydrochloric acid and thiourea solution were added,and dissolved at 110 ℃ for 35 minutes.After cooling,water was added to the mark to complete the sample digestion.Determine the detection limit,precision,spiked recovery rate,calculate the relative standard deviation(RSD),and perform standard substance determination.After determining the optimal experi-mental conditions,the total selenium content was determined using hydride atomic fluorescence spectrometry.Results Under optimized conditions,the linear range of tetravalent selenium was 1.00-10.00 μ g/L,r=0.999 7.The recovery rate of tetravalent selenium spiked ranged from 97.98％-101.00％,and the relative standard deviation(RSD)was 0.99％-1.28％.The recovery rate of hexavalent selenium spiked was 96.32％to 98.82％,with RSD ranging from 0.84％to 1.44％.The measured values of standard substances were within a reliable range.The minimum detection limit was 0.20 μg/L.Conclusion After optimizing the method for determining tetravalent selenium and hexavalent selenium in water u-sing hydride atomic fluorescence spectrometry in this experiment,the linearity,detection limit,precision,and accuracy of the measurement results all meet the methodological requirements.The constant temperature digestion method can accu-rately determine the total selenium content in water,and the operation is simple.
Total seleniumThioureaREDOX reactionHydride atomic fluorescence spectrometry
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维普
