采用功能化温控离子液体萃取-火焰原子吸收光谱法测定痕量镉。优化的试验条件如下:① 离子液体的用量为0.25 g;② 溶液的pH为5.81;③ 离心时间30 min;④ 反萃取剂为2 mol·L-1盐酸溶液5.00 mL;⑤ 超声时间为30 min;⑥ 反萃取3次。镉的质量浓度在1.20 mg·L-1以内与其吸光度呈线性关系,检出限(3s/k)为0.027 mg·L-1。方法应用于模拟水样的分析,测定值与参考值相符。加标回收率在102%~110%之间,测定值的相对标准偏差(n=3)均小于1.0%。

FAAS was applied to the determination of trace amount of cadmium with functional temperature-control-ionic liquid extraction. The optimized conditions found were as follows: ① amount of ionic liquid: 0.25 g; ② pH of the solution: 5.81; ③ time of centrifugation: 30 min; ④ amount of 2 mol·L-1 hydrochloric acid solution (back-extractant): 5. 00 mL; ⑤ time of ultrasonic extraction: 30 min; ⑥ times of back-extraction: 3. Linear relationship between values of absorbance and mass concentration of cadmium was obtained in the range within 1.20 mg·L-1,with detection limit (3s/k) of 0.027 mg·L-1. The proposed method was applied to the analysis of simulated water sample,giving results in consistency with the known value. Values of recovery found by standard addition method were in the range of 102%-110%,and values of RSD′s (n=3) less than 1.0%.