共振光散射法测定环境水样中痕量亚硝酸根

Determination of Trace Nitrite Ion in Environmental Water by Resonance Light-Scattering

研究了在磷酸介质中,亚硝酸根-碘化钾-结晶紫(CV)体系的共振散射光谱,考察了它们的光谱特征、影响因素和适宜的反应条件.确定了散射光强度与溶液中NO-2浓度的关系,提出了共振光散射测定NO-2的新方法.该方法在室温下即可进行,操作方便,具有较高的灵敏度和选择性.方法的线性范围为2.24-320μg LNO-2,方法的检出限为0.68μg LNO-2.用于环境水样中NO-2的测定,结果满意.

The spectrum of NO^-_2-KI-Crystal violet ion association complex has the resonance in phosphoric acid medium. Based on this phenomenon,the spectral characteristics, the effect factors and optimum conditions of the reaction have been investigated. The quantitative relationship between the intensity of resonance scattering to the concentration of nitrite ion was established. A new method for the determination of trace nitrite ion in water sample has been proposed. This method can be operated conveniently at ambient temperature. It showed a high sensitivity and good selectivity and had a good liner relationship within the range of 2.24～320μg/L NO^-_2and a detection limit of 0.68μg/L NO^-_2.This method has been applied to the determination of NO^-_2 in the environmental water and the result is satisfactory.