离子色谱法测定家庭饮用水中阴阳离子

Determination of Anions and Cations in Household Drinking Water by Ion Chromatography

目的建立离子色谱法测定家庭饮用水中常规阴阳离子的方法,为居民饮用水安全提供可靠数据。方法采用ICS-900型离子色谱仪测试水样中F^-、Cl^-、NO_3^-、SO_4^(2-)、PO_4^(3-)、Li^+、Na^+、NH_4^+、K^+、Mg^(2+) 和 Ca^(2+)共11种常规阴阳离子含量,测试时选择合适的仪器条件,对11份水样进行测定,阴离子分析条件为KOH淋洗液浓度10~40mmol·L^(-1)、抑制器电流99mA,阳离子仪器条件为甲烷磺酸淋洗液20mmol·L^(-1)、抑制器电流75mA,淋洗液流速均为1.0mL·min^(-1),进样量均为10μL。结果 3次测量取平均值且相对标准偏差均小于1%,表明离子色谱法测定水溶液中各阴阳离子准确、高效、误差小、重复性好。阴阳离子色谱柱在该试验条件下对各离子的分离效果较好,标准曲线相关性均在0.999以上。结论家庭生活中自来水水样中Mg^(2+)和Ca^(2+)含量较高,水体硬度较大,但符合生活饮用水水质标准。

ObjectiveTo provide reliable data for drinking water safety,method for the determination of anions and cations in drinking water by ion chromatography was established. Methods The 11 kinds of conventional antion and cation F^-,Cl^-,NO 3^-,SO 4^2- ,PO 4^3- ,Li^＋,Na^＋,NH^4 ＋,K ＋,Mg^2＋ and Ca^2＋ were monitored by the ICS-900 ion chromatography;the appropriate testing conditions of instrument were chosen;The anion analysis conditions for KOH eluent concentration was 10 mmol/L～40 mmol/L,and the suppressor current was 99 mA;the cation instrument conditions for the methane sulfonic acid eluent were 20 mmol/L,and 75 mA suppressor current;and the both eluent current speeds were 1.0 mL /min,and the sample quantity 10 μL.Results The average value of three measurements and the relative standard deviations were less than 1%.The results show that the ion chromatography method on the determination of antions and cations in aqueous solution was accurate and high-efficient with small-error and good repeatability.Under the above experimental conditions,the separation effect to each ion of ion chromatographic column was good,and the correlation coefficient of the standard curve was above 0.999. Conclusion The results indicated that the concentrations of Mg 2＋ and Ca 2＋ were higher in household tap water and the water hardness was higher,but the water quality was in accordance with the standard of drinking water quality.