阳极溶出伏安法连续测定底泥中的总镉和总铅

Continuously Determining the Total Cadmiums and the Total Plumbums in the Bottom Soil by the ASV Method

底泥样品经盐酸—硝酸—氢氧酸—高氯酸消解后,用1+1盐酸溶解残渣,以高氯酸做支持电解质,采用阳极溶出伏安法的标准加入法,连续测定样品中的总镉和总铅。该方法测定土壤标准样品中镉和铅的相对标准偏差分别为5．6％和4．6％,相对误盖分别为2．4％和-1．7％；测定自采底泥样品中镉和铅的相对偏差分别为7．7％和8．1％,方法的重复性好；测定土壤标准样品中镉加标回收率为94．0％～106．8％,铅加标回收率为95％～103．8％；自采样品中镉加标回收率为93．0％～105．6％,铅加标回收率为90．0％～105．0％,方法的准确度较高。实验中,镉和铅的半波电位稳定,峰形对称。

The bottom soil samples clear up after by hydrochloric acid- nitric acid- hydrofluoric acid- perchloric acid, dissolving the draft with 1 ＋ 1 hydrochloric acids, using the backup electrolyte with the perchlorie acid, then adopting the method of accede to standard liquid of the ASV method and continuously determining the total cadmiums and the total plumbums in the samples. The opposite standard deviation of the method to measure the cadmium and the plumbum in the standard sample of soil are 5.6% and 4.6%, the opposite error distinguishes to 2.4% with - 1.7%, the opposite standard deviation of the method to measure the cadmium and the plumbum in the bottom mire sample of soil are 7.7% and 8.1%, the method＇s counterpoint is good. Measure soil the cadmium in the standard sample to add the mark recovery rate as 94.0% - 106.8%, the plumbum adds a mark the recovery rate for 95% - 103.8%, add the mark recovery rate as 93.0% - 105.6% from the eadmium in the sample article, the plumbum adds a mark the recovery rate for 90.0% - 105.0%, the method＇s veracity is higher. In the experiment, the half wave electric potential of the cadmium and plumbom are stable, and the form of the apex is symmetry.