基体分离-电感耦合等离子体原子发射光谱法测定高纯钼中9种元素

利用电感耦合等离子体原子发射光谱法(ICP-AES)测定高纯钼样品中杂质元素含量时,由于钼元素具有丰富的谱线,因此钼基体对待测元素干扰较大。为了消除钼基体对待测元素的干扰,实验使用过氧化氢溶解样品,过量硝酸沉淀分离钼基体作为样品前处理步骤,建立了基体分离-电感耦合等离子体原子发射光谱法测定高纯钼中钙、铬、铜、钴、镁、镍、锌、镉和锰的方法。使用4mL过氧化氢溶解样品,10mL硝酸沉淀钼基体,钼的沉淀效率大于99%,沉淀后,各待测元素背景等效浓度均有下降,且回收率都高于85%,随沉淀损失较少。使用高纯钼基体沉淀分离的方法配制校准曲线,各待测元素校准曲线线性相关系数均大于0.999 7;方法中各元素的定量限为0.20～2.03μg/g。实验方法用于测定高纯钼样品中钙、铬、铜、钴、镁、镍、锌、镉和锰,结果的相对标准偏差(RSD,n=5)为2.0%～4.8%,测定结果与电感耦合等离子体质谱法(ICP-MS)结果一致。

Determination of nine elements in high purity molybdenum by matrix separation-inductively coupled plasma atomic emission spectrometry

During the determination of impurity elements in high purity molybdenum sample by inductively coupled plasma atomic emission spectrometry (ICP-AES), the matrix molybdenum had great interference with the determination of elements due to the abundant spectral lines of molybdenum. In order to eliminate the interference of matrix molybdenum with the determination of elements, the following pretreatment procedures were used: the sample was dissolved with hydrogen peroxide, then the matrix molybdenum was separated by precipitation with excessive nitric acid. The determination method of calcium, chromium, copper, cobalt, magnesium, nickel, zinc, cadmium and manganese in high purity molybdenum by matrix separation-inductively coupled plasma atomic emission spectrometry was established. The sample was dissolved with 4mL of hydrogen peroxide. The matrix molybdenum was precipitated with 10mL of nitric acid, and the precipitation efficiency was higher than 99%. After precipitation, the background equivalent concentrations of elements were all decreased. The recoveries were higher than 85% and the loss due to precipitation was low. The calibration curve was prepared using high purity molybdenum by the method of matrix separation. The linear correlation coefficients of calibration curves of all elements were higher than 0.9997. The limits of quantification were between 0.20μg/g and 2.03μg/g. The proposed method was applied for the determination of calcium, chromium, copper, cobalt, magnesium, nickel, zinc, cadmium and manganese in high purity molybdenum sample. The relative standard deviations (RSD, n=5) of the results were between 2.0% and 4.8%. The found results were consistent with those obtained by inductively coupled plasma mass spectrometry (ICP-MS).