浊点萃取预富集-火焰原子吸收光谱法测定环境水中钴

以浊点萃取为分离富集方法，以火焰原子吸收光谱法为检测手段，探讨了测定钴的新方法。以非离子型表面活性剂OP-8为萃取剂，同时以1-（2-吡啶偶氮）-2-萘酚为络合剂，浊点萃取水样中的痕量钴（Ⅱ）。对溶液pH值、试剂浓度、平衡温度和时间、离心时间等实验条件进行了优化。钴的质量浓度在1．00mg／L以内与其吸光度呈线性关系，检出限（3σ）为0．26／μg／L，相对标准偏差为2．5％（P=0．4mg／L，n=5次）。该法用于自来水、河水、湖水以及雨水中痕量钴的测定，回收率在96．0％-103．0％，结果令人满意。

Determination of cobalt in environmental water by flame atomic absorption spectrometry via cloud point extraction

A new method is proposed to determinate the trace cobalt in water samples by flame atomic absorption spectrometry after separation and enrichment via cloud point extraction. The CPE behavior of cobalt using as complex agent 1-（2-pyridylazo）-2-naphthol and OP-8 as nonionie surfactant are in- vestigated systematically. Various experimental parameters for instance pH, concentration of rea- gents, equilibration temperature and time, centrifugal time are optimized. There is a linear relation- ship between absorbance and cobalt concentration in the range of 1.0 mg/L. The detection limit （3σ） is 0.26μg/L for cobalt with relative standard deviation of 2.5% （ p =0.4 rag/L, n =5）. The new method is applied into the determination of trace cobalt in water samples with the recovery of 96 % 103 % and it has an ideal result.