原子荧光光谱法测定微量元素预混料中砷含量的方法改进

Improvement of the method for detecting the content of arsenic in the trace element premix with atomic fluorescence spectrometry

[目的]改进样品前处理方法后,采用改进后的原子荧光光谱法检测微量元素预混料中的砷含量,以提高检测结果的准确性。[方法]用湿法消解微量元素预混料样品后,在样品溶液中加入适量的氢氧化钠溶液,使样品溶液中的Cu^(2+)、Fe^(3+)等干扰因子和氢氧化钠反应生成氢氧化铜、氢氧化铁等沉淀物质,通过离心去除其干扰因子,再检测样品中的砷含量。[结果]原方法测定的结果稳定性差,改进后,检测结果稳定性好,加标回收率较高。[结论]采用改进后的方法测定砷含量的结果更准确。

[Objectives]After improving pretreatment methods of the sample,the improved atomic fluorescence spectrometry was used to detect the content of arsenic in the trace element premix to im-prove the accuracy of the detection results.[Methods]After wet digestion of the pre-mixed sample of trace elements,an appropriate amount of sodium hydroxide solution was added to the sample solution,causing interference factors including Cu^(2+)and Fe^(3+)in the sample solution to react with sodium hydrox-ide to generate precipitates such as copper hydroxide.The interference factors were removed by cen-trifugation,and then the content of arsenic in the sample was detected.[Results]The stability of the results determined by the original method was poor.The stability of the results detected with the im-proved method was good.The recovery rate of the added standard was high.[Conclusions]The im-proved method is more accurate in determining the content of arsenic.