电感耦合等离子体原子发射光谱法测定高纯氧化铌中13种杂质元素

ICP-AES Determination of 13 Impurity-Elements in High-Purity Niobium Oxide

1.000 g试样置于PTFE消解罐中,加入氢氟酸2 mL,在120℃和大于138 kPa的压力下于MARS 5微波消解系统中消解20 min,所得溶液稀释至100 mL,供电感耦合等离子体原子发射光谱测定用。采用基体匹配法,即在制作校正曲线的各试验点中加入一定量的基体元素铌,消除了基体效应。对各元素分析谱线的选择和背景校正等对测定有影响的因素也进行试验并提出了解决方法。分别对方法的回收率、精密度及检出限也进行了试验,测得回收率在90%～120%之间,相对标准偏差(n=6)在1.0%～10.0%之间,检出限(3σ)在1.3～42.0μg·L^(-1)之间。

1. 000 g of Nb2O5 was digested with 2 mL of HF at 120 ℃ and under a pressure larger than 138 kPa for 20 rain in the MARS 5 Microwave Disgestor. The sample solution obtained was diluted to 100 mL in a volumetric flask, and used for AES determination. Matrix effect of niobium was eliminated by matrix matching method, i. e. a definite amount of niobium was added to each of the test solutions in preparation of calibration curve. Some other influential factors, including the choice of analytical spectral lines, background correction and etc. , were also studied, and optimized. Test for recovery was made by adding different amounts of standard solutions of the 13 elements to niobium matrix, and values of recovery obtained were in the range of 90%-120%, and values of RSD＇s （n=6） found were in the range of 1. 0%-10. 0%. Detection limits （3a） of the method for the 13 elements were in the range of 1.3 to 42.0μg ·L^-1.