离子色谱法测定水中阴离子的质量控制

目的 为消除和减小离子色谱法测定水中阴离子(Cl-)的实验误差,保证测量结果的准确性和可比性.方法 选用Metrosep A SUPP 4(4.0mm×250 mm)阴离子色谱柱,1.7 mmol/L Na2HCO3和1.8 mmol/L Na2CO3淋洗液为流动相,流速为1.0 ml/min,抑制型电导检测器,经0.45.μm滤膜过滤后,进样检测.结果 测得Cl-在5.0 ～100 mg/L范围内线性关系好,相关系数r=0.9997,加标回收率为98.4％～101.0％,RSD在0.000 9％ ～0.002 9％间,对水中4种阴离子F-、Cl-、NO3 -、SO42-同时分析,相关系数均大于0.9990；具有良好的准确度和精密度.结论 经过实施全面有效的质量控制措施,Cl获得满意结果,在实际工作应用中,能较好地监控农村饮用水中阴离子的分布动态.

Quality Control of Determination of Anions in Water by Ion Chromatography

[Objective]To eliminate and reduce the error of the ion chromatography method for determination of anion,and guarantee the accuracy of the measurement results and comparability. [Methods]The methods was based on the detection through the inhibited type electric conductivity detector under the condition of eluent with 1.7 mmol/L NaHCO3 and 1.8 mmol/L Na2CO3 as mobile phase and flow rate 1.0ml/min,filtering through the 0.45 μm membrane filter by using of the Metrosep A SUPP 4（4.0×250 mm） Anionic chromatography column. [Results]This method had a good relativity（r=O.999 7）,and the Cl-curve showed good linearity in the range of 5.0-100 mg/L.The recoveries was between 98.4%~101%,RSDwas between 0.000 9%～0.002 9%,and the correlation coefficient was greater than 0.999 by analyzing the F-,Cl-,NO-3 and SO42-in water,and the detection method had good accuracy and precision. [Conclusion]After the implementation of the comprehensive and effective quality control measures,Cl shows satisfactory results,during the actual work application,the distribution of anion dynamic in rural drinking water can be monitored well.