离子色谱法同时测定纯化水和饮用水中亚硝酸盐和硝酸盐

目的:建立离子色谱法同时测定纯化水和饮用水中亚硝酸盐和硝酸盐的含量的方法。方法:以物质的量浓度为3.2 mmol/L的Na₂CO₃和物质的量浓度为1.0 mmol/L的NaHCO₃为淋洗液,以物质的量浓度为50 mmol/L的硫酸为再生液,采用MIC型离子色谱仪,METROSEP A SUPP 5-250柱分离,电导检测器检测,外标法定量。结果:亚硝酸盐:线性范围0.05 mg/L～2.0 mg/L,相关系数0.999 5,样品加标回收率为97.33%～98.67%,RSD为0.6%～1.2%,检出限为0.001 mg/L,定量限为0.002 mg/L;硝酸盐:线性范围0.01 mg/L～1.0 mg/L,相关系数0.999 3,样品加标回收率为95.44～97.04%,RSD为0.5%～0.7%,检出限为0.001 mg/L,定量限为0.002 mg/L。结论:该方法灵敏、快捷,能够用来同时测定纯化水和饮用水中亚硝酸盐和硝酸盐的含量,适用范围广。

Simultaneous determination of nitrite and nitrate in purified water and drinking water by ion chromatography

Na₂CO₃ with molar concentration of 3.2 mmol/L and NaHCO₃with molar concentration of 1.0 mmol/L were used as eluent,and sulfuric acid with molar concentration of 50 mmol/L was used as regeneration fluid.The separation was carried out on METROSEP A SUPP 5-250 column,and was determined by ion chromatography of switzerland wantong with conductivity detector.External standard method was used for quantification.The results showed that,the linear range of nitrite nitrogen was 0.05 mg/L-2.0 mg/L,the correlation coefficient r=0.9995,the recoveries were in the range of 97.33%-98.67%,the RSDs were in the range of 0.6%-1.2%,the detection limit was 0.001 mg/L and the quantitative limit was 0.002 mg/L;the linear range of nitrate nitrogen was 0.01 mg/L-1.0 mg/L,the correlation coefficient r=0.9993,the recoveries were in the range of 95.44%-97.04%,the RSDs were in the range of 0.5%-0.7%,the detection limit was 0.001 mg/L and the quantitative limit was 0.002 mg/L.The proposed method is sensitivity,fast,and widely applicable.