微分电位溶出法测定饮用水中铅、铜和镉的研究

目的研究微分电位溶出法在底液为0.01 mol/L HCl条件下,连续测定饮用水中铜、铅和镉3种痕量元素的方法。方法通过优化实验条件,采用DPSA-2型微分电位溶出仪对饮用水中铜、铅和镉进行连续测定。结果铜、铅和镉的检出限分别为4、0.1、2μg/L,线性测定范围为0～220μg/L,回收率为83.4%～103.3%,RSD〈3.4%（n=7）。结论该方法一次镀汞可连续使用,具有操作简便、快速,灵敏度、准确度高和精密度好等特点,该法较好地解决了金属互化物的影响,样品不需消化便可直接测定。由于该法对样液中的电活性物质干扰不敏感,因此,试样只要进行酸化处理即可直接测定。

Determination of Lead, Copper and Cadmium in Drinking Water by DPSA

[Objective]To study the differential potentiometric stripping analysis（DPSA） in continuous determination of trace elements of lead,copper and cadmium in drinking water under the condition of 0.01 mol/L HCl for base solution.[Methods]With optimized experimental conditions,DPSA-2 was applied for the continuous determination of lead,copper and cadmium in drinking water.[Results]The detection limits of lead,copper and cadmium was 4,0.1,2 μg/L respectively,the linear range was 0～220 μg/L,recoveries were 83.4%～103.3%,RSD〈3.4%（n=7）.[Conclusion]This method is serially reusable after plating of mercury for 1 time,with characteristics of simple,rapid,high sensitivity and accuracy,and good precision,solve the intermetallic effect well,can directly determine the samples without digestion.Due to the insensitivity of this method to interference of electroactive substance in sample solution,the sample can be directly determined with acidification.