氢化物发生-原子荧光光谱法同时测定饮用水中砷和硒

目的研究采用氢化物发生-原子荧光光谱同时测定饮用水中砷和硒的方法。方法对氢化物发生-原子荧光光谱法同时测定饮用水中砷和硒的仪器参数条件：灯电流、负高压、原子化器高度、载气流速及其他因素：载流盐酸浓度、硼氢化钠浓度、硫脲-抗坏血酸混合液浓度及共存离子干扰等进行研究。结果方法的荧光强度与砷和硒质量浓度分别在0.3～100ug/L及0.2～80ug/L范围内呈线性关系（r=0.9999,r=0.9998）。方法的检出限为砷：0.07ug/L;硒：0.04ug/L。方法的精密度试验RSD〈2%。2标准物质的测定值均在标准物质标准值不确定度范围内。应用此法对自来水、井水、河水、池塘水样品进行测定,并作加标回收率实验,测得砷和硒的回收率均在96.2%～104.0%。结论本文建立的氢化物发生-原子荧光光谱法同时测定砷和硒,方法简便、快速,结果准确可靠。

Simultaneous Determination of As and Se in Drinking Water by Hydride Generation-Atomic Fluorescence Spectrometry

Objective To study application of the simultaneous determination of Arsenic and Selenium in drinking water with HG - AFS. Methods Researching the working condition of instrument, including lamp current negative high - voltage, the rate of carrier and shield gas was described in detail. Other factors including the concentration of Hydrochloric acid, the concentration of Sodium borohydride, the concentration of mixed solution of thiourea and ascorbic acid and interferences of the coexisting ions were studied. Linear relationships between the fluorescence intensity and mass concentration of As and Se found were in the ranges of 0.3 - 100ug/L and 0.2 - 80ug/L （ r = 0.9999 r = 0.9998 ）, with the detection limits of 0.07ug/L and 0.04ug/L, respectively. Values of RSD of the method found were less than 2%. The analytical results of two Reference Materials were in uncertainty. The proposed method was applied to the analysis of samples of tap water, well water, river water and pond water. Use these samples as matrixes, tests for recovery were made by standard addition method, values of recovery for As and Se were ranged in 96.2% - 104.0%. Conclusions The study showed that the simuhaneous determination of arsenic and Selenium in drinking water with HG - AFS was easy to practise and resnlts had good accuracy and reliability.