A Simple and Sensitive Spectrophotometric Determination of Nitrate and Nitrite in Water Samples

The spectrophotometric method presented here was developed to provide information about the concentrations of nitrate and nitrite ions during the catalytic reduction of nitrate in drinking water. For the determination of nitrate, the absorbance is measured at 220 nm and HCl is used as the sole reagent. For the determination of nitrite, a method in which a peroxovanadate complex is decolorized by nitrite, was employed as basis for the quantitative determination of this ion in water samples. The calculated concentrations of NO₂ - and NO₃ - agree with the true concentrations within 5% for NO₃ - and 1% for NO₂ -, showing that the developed method is useful for the determination of both components. The results obtained with the proposed method agree well with those obtained by the standard IC method.