用ICP-AES测定三烷基氧膦(TRPO)-煤油体系中的稀土元素

研究了以乙醇作为稀释剂直接有机溶液ICP-AES进样测定30%三烷基氧膦(TRPO)-煤油体系中的稀土元素。30%三烷基氧膦(TRPO)-煤油含量在4%~20%之间变化时稀土元素的谱线强度变化缓慢。随着水含量在1%~7%内的增加,稀土元素La,Pr,Nd和Sm的谱线强度略有下降,而Ce随着水含量的增加而增加。HNO3浓度在0.065~0.315 mol.L-1范围内对稀土元素的相对谱线强度的影响不大。同时研究了元素Fe和Zr在该体系中对稀土元素的基体干扰问题,Fe对稀土元素的干扰不显著,但当Zr的浓度大于稀土元素10倍时,稀土元素Ce,Pr和Nd的相对谱线强度受到一定程度的干扰。该方法的应用范围即30%三烷基氧膦(TRPO)-煤油含量在4%~20%为宜,稀土元素La,Ce,Pr,Nd,Sm检测限分别为0.012,0.040,0.029,0.040,0.021μg.mL-1,相对标准偏差小于2%;且与湿法消化法相比该方法的相对误差小于3%。该方法与无机消解水溶液进样ICP-AES法相比,该方法操作简单、快速,可以满足分析的要求。

Determination of Rare Earth Elements in Trialkyl Phoshine Oxide(TRPO)-Kerosene by ICP-AES

The present paper describes the determination of rare earth elements (REEs) in 30% TRPO-kerosene by inductively coupled plasma atomic emission spectrometry (ICP-AES) with ethanol as diluent. The relative intensities of REEs vary slowly when the content of 30% TRPO-kerosene varies from 4% to 20%. The relative intensity of Ce increased with the contents of H2O increasing from 1% to 7%, but the other REEs did not vary. No effects on the relative intensities of REEs are seen when the concentration of HNCO3 varies from 0.065 to 0.315 mol x L(-1). The effects of Fe and Zr on the relative intensities of REEs are also investigated. The effects of Fe on the relative intensities of REEs are not obvious, but when the concentration of Zr is ten times larger than REEs, the effects are obvious. The method is applicable when the content of 30% TRPO-kerosene ranges from 4% to 20%, the limits of detection of La, Ce, Pr, Nd, Sm are 0.012, 0.040, 0.029, 0.040 and 0.021 microg x mL(-1) respectively, the RSD% is lower than 2%, and the relative error is lower than 3% when compared with the determination result of digestion. In contrast with digestion, this method is simple and rapid, and can accord with the requests of analysis.