ICP-MS同时测定复混肥料中16种稀土元素

Determination for 16 kinds of rare earth elements in the compound fertilizers by using ICP-MS

【目的】建立电感耦合等离子体质谱仪（ICP-MS）测定肥料中稀土元素的方法,为科学调查复混肥料中稀土元素含量提供技术支持。【方法】分别采用微波消解和电热板消解方法进行前处理,采用ICP-MS测定Sc、Y、La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu等16种稀土元素在复混肥料样品中的含量。【结果】ICP-MS测定16种稀土元素的检出限为2.9~72.0 ng/kg,标准曲线的线性关系良好,相关系数≥0.9994。前处理使用微波消解和电热板消解的加标回收率分别为92.87%~109.17%和85.96%~119.06%,相对标准偏差（RSD）〈0.70%。随机抽检的10种复混肥料中稀土元素含量范围为3.3400~38.3500 mg/kg,平均含量17.0500 mg/kg,稀土元素最高含量是最低含量的11.48倍。【结论】以ICP-MS测定复混肥料中稀土元素具有易于操作、选择性好、灵敏度高、定量准确等优势,可在复混肥料稀土元素的环境安全评价中推广应用。

【Objective 】The inductively coupled plasma-mass spectrometry（ICP-MS） method for determining of rare earth elements（REEs） in compound fertilizer were established, in order to provide technical supported for scientific investigation of REEs contents in compound fertilizer. 【Method】The samples were digested by microwave digestion method and electric heating plate digestion method. The contents of REEs including Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy,Ho, Er, Tm, Yb, Lu in the compound fertilizer samples were determined by using ICP-MS. 【Result】The detection limits of 16 REEs were 2.9-72.0 ng/kg when using ICP-MS to determine REEs contents, and the determination method had good linear relationship, with correlation coefficients of more than or equal to 0.9994. The standard addition recovery using microwave digestion method ranged from 92.87% to 109.17%, the standard addition recovery using electric heating plate digestion ranged from 85.96% to 119.06%, and the relative standard deviation（RSD） was less than 0.70%. The contents of rare earth elements in 10 kinds of compound fertilizers ranged from 3.3400 to 38.3500 mg/kg, with an average content of 17.0500 mg/kg, the highest content of rare earth element was 11.48 times higher than the lowest content. 【Conclusion】ICP-MS determination of rare earth elements in compound fertilizers has advantages of easy operation, good selectivity, high sensitivity and accuracy. It can be popularized and applied in environmental safety assessment of rare earth elements.