CTMAB-Peregal O存在下锌镉的FIA同时测定

Simultaneous FIA Spectrophotometric Determination of Zinc and Cadmium in the Presence of Mixed Surfactants

混合表面活性剂CTMAB-Peregal O对Zn^(2+)和Cd^(2+)与4-(2-吡啶偶氮)一问苯二酚的配合反应有协同增敏作用。由配合反应测得Zn^(2+)和Cd^(2+)的总量,用二乙基二硫代氨基甲酸钠掩蔽Cd^(2+)后,可测得Zn^(2+)量,再由计算求得Cd^(2+)量。研究了应用连续交替注入技术流动注射光度法同时测定Zn^(2+)和Cd^(2+)的方法。Zn”和Cd^(2+)的浓度分别在0～0.6μg/g和0～1.0μg/g时符合比耳定律。相对标准偏差<1.0%,进样频率180次/h。曾用此法测定了西湖水和工业废水中的Zn^(2+)和Cd^(2+),结果满意,并初步探讨了协同增敏作用的机理。

In the presence of mixed surfactants (CTMAR-Peregal O), the color reactions of Zn and Cd with 4-(2-pyridylazo)-resorcinol (PAR) are sensitized. The total amounts of Zn and Cd could be determined. After masking Cd with diethyldithiocarbamate, Zn could be determined directly, and then amounts of Cd could be calculated. In virtue of the technique of sequential injection, a new method of simultaneous determination of Zn and Cd in the same sample was developed. Beer's law is obeyed for Zn in the rang of 0.0～0.6μg/g and for Cd 0.0～1.0μg/g. RSD<1.0%. Sampling frequency was 180s/h. By this method Zn and Cd in West lake water and industrial waste were determined. The sensitization mechanism of mixed surfactants was discussed.