顺序注射氢化物发生-原子荧光光谱法同时测定环境水样中砷和镉

Determination of Arsenic and Cadmium in Water by Sequential Injection Hydride Generation Atom Fluorescence Spectrometry

目的考察了光电倍增管负高压、砷和镉灯电流、原子化器高度、载气流量、屏蔽气流量、增敏剂等因素对测定结果的影响。方法建立一种顺序注射氢化物发生-原子荧光光谱法同时测定水样中砷和镉含量的方法。结果载流HCl的浓度为0.60 mol/L,KBH4质量浓度为20g/L,增敏剂硫脲和钴离子的质量浓度分别为80 g/L和70 g/L时,同时测定砷和镉的效果最佳。在最佳实验条件下,砷和镉的检出限分别为0.009 3μg/L和0.12μg/L,加标回收率为92.3%～103.9%,相对标准偏差小于3.5%,被测水样中共存离子对砷和镉的测定没有干扰。结论该法操作方便、快速,用于环境水样中砷和镉的同时测定,具有很好的可行性和实用性。

Objective To establish a method for simultaneous determination of arsenic and cadmium in water by sequential injection hydride generation -atomic fluorescence spectrometry. Method The influence of instrument parameters such as the negative high voltage on the photomuhiplier, current of lamp, carrier gas rate, shield gas rate, sensitizer on the determination of arsenic and cadmium were studied. Result When the concentration of hydrochloric acid and potassium borohydride were 0.60 mol/L and 20 g/L respectively, the concentration of sensitizer sulfocarbamide and Co2＋ were 80 g/L and 70 mg/L respectively, the effect of determination of arsenic and cadmium was perfect. Under the proposed conditions, the detection limits of arsenic and cadmium were 0. 009 3 μg/L and 0. 12 μg/L respectively. The standard addition recoveries for arsenic and cadmium were 92.3% - 103.9%. The maximum RSD found was 3.5%. The coexistence ions in determined water samples did almost not interfere in the determination of arsenic and cadmium. Conclusion The operation of this method was easy and its sensitivity was higher. There are feasibility and practicability to determine arsenic and cadmium in water.