Improvement on Method for Determination of Iodide in Drinking Water by Catalytic Reducing Spectrophotometry / 环境与健康杂志

ABSTRACT

ve To explore and improve the procedures of operation and experimental conditions of deter-mination of iodide in drinking water by catalytic reducing spectrophotometry. Methods The improved assay was carried out at room temperature instead of constant temperature water bath. The standard solution series [1~10?g/L or 10-100?g/L iodine(I-) ] were selected based on the contents of iodide in water samples estimated by "three-tube method" . The duration of catalytic reducing reaction was defined based on the decolorant intensity of Ce4+ observed by visual method. The linear regression equation of Ig E0/Ef ; (Eo blank absorbance; Ei standard absorbance) was used to replace the nonlinear standard curve of absorbance. Results The contents of iodide in blind water sample of analytical quality control determined by this method highly accorded with its ture value [(4.00?0.20)mg/L]provided by institution of analytical quality control. The linear regression equation of standard solution series was calculated by lg E0/Ei as y = 0.062x + 0.018(r = 0.999) . Conclusion The improved assay simplifying analytical instruments and operations was suitable for determination of iodide in drinking water in common laboratories.