Study on Determination of Hexavalent Chromium in Water by Ultraviolet Spectrophotometry
The national geological method for the determination of hexavalent chromium in water by ultraviolet spectrophotometer was discussed,the suspension in the sample was eliminated,and the reagent was added for the sample processing on the basis of the original method.Although dried filtration can measure the hexavalent chromium in the water,and the filtering process is relatively simple,the chromium is mainly in the form of three-valent and six-valent in the water,and it exists in the dissolved state and granular in the water,so that the measured result after filtering is low.In this article,the hexavalent chromium was determined by improved UV lighting method.The samples of national standard solutions with different water quality components were analyzed,and the results showed that the repeatability qualified rate of the method reached 98%,and the recovery rate was also between 95%and 104%.The accuracy,precision and recovery rate of the analysis results met the requirements.The detection limit of this method was 0.004 mg·L-1 and the RSD(n=12)was less than 6%.The test results with dry filtration and without filtration and before and after adding reagent were compared.The results showed that the relative error was less than 6%when adding reagent without filtration,which was consistent with the recommended value.
Hexavalent chromiumWater qualityUltraviolet lighting meter
万方数据
维普
