电感耦合等离子体质谱法测定高纯氧化钕中的稀土杂质

Determination of Impurities in High Pure Neodymium Oxide with Inductively Coupled Plasma Mass Spectrometry

基于电感耦合等离子体四极杆质谱仪进行Nd2O3中稀土杂质测定,着重研究了碰撞反应池技术(CCT)用于基体Nd氧化物和氢氧化物干扰离子的消除。研究表明,以10%O2-10%Ar-80%He为碰撞反应气,保持反应气流速为0.1 mL/min,并通过调谐仪器参数,获得159Tb,165Ho,163Dy同位素的175TbO,179DyO和181HoO出现强氧化物峰,通过对这些氧化物离子进行检测而实现Tb,Dy,Ho的定量分析。在优化的条件下,基体导致的氧化物和氢氧化物质谱干扰可降低25～70倍。研究了CCT模式下不同内标元素用于基体效应的校正。结果表明,Re的校正效果最佳。其余La,Ce,Pr,Sm,Eu,Gd,Er,Tm,Yb和Lu等元素采用常规模式测定,其中Pr的测定采用高分辨以消除基体Nd前沿峰干扰。结合干扰系数校正,所建立的方法适用于99.999%Nd2O3的纯度分析,RSD小于5%,加入回收率令人满意。

A method for the determination of impurities in high pure Nd2O3 employing inductively coupled plasma mass spectrometry （ICP-MS） was established, and emphasise was put on the elimination of matrix induced NdO^＋ and NdOH^＋ spectral interferences using cell collision technology（CCT）. Using 10% O2-10% Ar-80% He as the reaction/collision gas and with proper adjustment of the instrumental parameters, ^159Tb,^165Ho,^163Dy could be quantified at ^175TbO,^179DyO and ^181HoO respectively, while the matrix induced NdO^＋ and NdOH^＋ spectral interferences could be reduced by 25-70 folds. In addition, different elements were tested as internal standards for matrix effect correction under the CCT mode, and it was found that Re was best. Other impurities including La, Ce, Sm, Eu, Gd, Er, Tm, Yb and Lu were detected under conventional mode, except that Pr was detected under high instrumental resolution mode to eliminate peak tailing interference from Nd. In combination with mathematic correction, the established method can be applied for the determination of impurities in 99.999% Nd2O3 products with satisfactory RSDs and recoveries.