浊点萃取-石墨炉原子吸收光谱法测定环境水样中痕量铬（Ⅵ）和总铬

提出了吡咯烷基二硫代甲酸铵（APDC）浊点萃取-石墨炉原子吸收光谱法测定痕量铬（Ⅵ）和总铬的新方法，详细探讨了溶液pH、试剂加入量等实验条件对浊点萃取及测定灵敏度的影响．在最佳条件下，富集10mL样品溶液，用石墨炉原子吸收光谱法测定铬（Ⅵ）的检测限为0．021μg／L，铬的富集倍率为20倍．方法用于环境水样中痕量铬（Ⅵ）和总铬的测定，获得了满意的结果．

Determination of trace chromium(Ⅵ)and total chromium in water samples by furnace atomic absorption spectrometry after cloud point extraction

A new method of determing trace amount of Cr （VI） and total chromium in water by graphite furnace atomic absorption spectrometry after cloud point extraction with ammonium pyrrolidine dithiocarbamate （APDC） was proposed. The effect of experimental conditions such as pH and concentration of reagents on cloud point extraction and determination sensitivity was discussed. The chemical variables affecting the separation phase and extraction recovery were optimized. Under the optimum conditions, pre-concentration of only 10 mL of sample in the presence of 0.05% Triton X-114 permitted the detection of 0. 021μ g/L （3α） for chro- mium. The enhancement factor was 20 for chromium. The proposed method had been applied to the determination of Cr（VI ） and total chromium in water samples and obtained satisfactory recoveries.