离子色谱法测定饮用水中亚硝酸盐和溴酸盐含量的变化

Determination of Trace Nitrite and Bromate in Pure Water Samples by Ion Chroma Tography

[目的]探讨饮用水中亚硝酸盐(NO2-)和溴酸盐(BrO3-)含量的变化。[方法]利用ICS-2000离子色谱法检测了3种饮用水中亚硝酸盐和溴酸盐在不同条件下的含量。[结果]在自来水、桶装纯净水、桶装矿泉水3种水中,亚硝酸盐含量随时间的增加有所增加,加热也未降低亚硝酸盐含量;纯水、自来水中未检测出溴酸盐,桶装矿泉水中测得的溴酸盐均随着时间的增加而增加,加热后能够较大程度上降低桶装矿泉水中溴酸盐的浓度。该方法检测的NO2-浓度在0～2 mg/L范围内有良好的线性关系(r=0.999 95),最小检测值为0.000 1 mg/L,实样加标回收率在97.34%～108.61%;BrO3-浓度在0～2 mg/L范围内也有良好的线性关系(r=0.999 97),最小检测值为0.000 2 mg/L,实样加标回收率在95.93%～101.04%。[结论]该方法精密度高、操作简便、易推广。

[Objective]Changes of trace nitrite and bromate in pure water samples were explored.[Method]Contents of trace nitrite and bromate in three kinds of pure water samples under different conditons were determined by using ICS-2000 ion chromatography.[Result]The contents of nitrite in three samples of tap water,bottled water and bottled mineral water increased with the increase of time,but didn＇t decrease under the treatment of heating.There was no bromate in pure water and tap water;the content of bromate in bottled mineral water also increased with the increase of time,and could be decreased to a much greater extent after heating.Nitrite showed good linear relationship within 0～2 mg/L（r=0.999 95）;the minimum detection value was 0.000 1 mg/L;and the sample standard addition was 97.34%~108.61%.Bromate also showed good linear relationship within 0～2 mg/L（r=0.999 97）;the minimum detection value was 0.000 2 mg/L;and the sample standard addition was 95.93%~101.04%.[Conclusion]The method has high accuracy,simple operation and application.