氢化物发生-原子荧光光谱法测定硒中痕量锑

Determination of trace antimony in selenium by hydride generation-atomic fluorescence spectrometry

硒样品经硝酸和盐酸溶解后,加入氯化羟胺将硒?还原成单质硒,使基体与杂质元素分离,用氢化物发生-原子荧光光谱法测定样品中锑。研究了氢化物发生的介质和酸度、硼氢化钾溶液浓度、预还原剂用量、预还原时间、氯化羟胺用量对测定结果的影响,确定了最佳测定条件。干扰试验表明硒样品中共存元素对测定无干扰。在最佳条件下,锑浓度在0～100ng/mL范围内与荧光强度呈良好线性关系,相关系数大于0.999 5,方法的检出限为0.23ng/mL。将方法应用于实际样品分析,测得结果和电感耦合等离子体原子发射光谱法(ICP-AES)基本一致,相对标准偏差(n=11)小于10%。

After the selenium sample was dissolved with nitric acid and hydrochloric acid,hydroxylammonium chloride was added to reduce selenium to elementary selenium,realizing the separation of matrix from impurity elements.Then,the content of antimony in sample was determined by hydride generation-atomic fluorescence spectrometry.The effects of medium and acidity in hydride generation,potassium borohydride concentration,dosage of pre-reduction reagent,pre-reduction time and dosage of hydroxylammonium chloride on the determination results were investigated.The optimal determination conditions were obtained.The interference test showed that the coexisting elements in selenium sample had no interference with the determination.Under the optimal conditions,the concentration of antimony in range of 0-100 ng/mL had good linearity to the fluorescence intensity with correlation coefficient higher than 0.999 5.Detection limit of this method was 0.23 ng/mL.The proposed method has been applied to the analysis of actual samples.The determination results were consistent with those obtained by inductively coupled plasma atomic emission spectrometry（ICP-AES） with relative standard deviation（RSD,n=11） less than 10 %.