光谱学与光谱分析, 2017, 37 (4): 1259, 网络出版: 2017-06-20  

ICP-MS法测钪的干扰研究及选冶尾矿中钪的直接测定

Study on the Interferences and Direct Determination of Sc in Metallurgical Tails with Inductively Coupled Plasma Mass Spectrometry
作者单位
1 北京科技大学化学系, 北京 100083
2 包头稀土研究院, 内蒙古 包头 014030
摘要
白云鄂博矿经选铁后, 尾矿中钪含量可达0.05%, 具有很高的开发利用价值。 建立了一种操作简便、 灵敏度高并能够准确测定尾矿及富铌渣中微量钪的电感耦合等离子体质谱(ICP-MS)测定方法。 对仪器参数、 试样处理方法、 共存元素的干扰和消除方法进行了系统研究, 选用铯、 铊和铑作为内标元素, 对非谱干扰加以校正。 对质谱干扰研究表明, 尾矿中的硼、 硅、 钙、 锆和铝均可能对钪的测定造成质谱干扰, 其中硼浓度较低(<100 μg·mL-1)时, 对钪测定没有明显干扰, 在测定条件下铝和钙的干扰较小, 可以忽略。 锆和硅的质谱干扰较严重, 其中锆的干扰为双电荷(90Zr++)干扰, 由于双电荷离子电离产率一般不高, 锆含量低时干扰可忽略, 锆的含量较高时, 采用公式c′=0.021c(Zr)-0.55对结果加以校正。 硅的干扰为氧化物干扰, 而硅氧键解离能大, 硅的氧化物(28Si17O+, 29Si16O+)稳定性高, 且相关同位素丰度较大, 在测定条件下干扰较严重, 可以采用式c″=0.013c(Si)+0.019扣除该影响。 选择了四种不同的样品处理方式, 结果表明采用HCl+HF+H2SO4混酸方法处理, 标样测定结果与标准值一致, 且能有效的克服硅和硼的质谱干扰, 同时降低了测定液的含盐量, 减小了非质谱干扰, 标样回收率在97%~99%之间。 标准样品及实际样品测定表明, 采用ICP-MS法直接测定白云鄂博选冶尾矿中钪含量, 结果准确, 相对标准偏差小于5%, 方法测定下限为0.000 1%。
Abstract
After the mineral dressing of iron ore from Bayan Obo ore, the content of scandium is up to 0.05% in tailings, which make it very valuable for utilization. A method for determine the trace scandium in the tailings and Niobium-rich slag with ICP-MS was established in this paper as a simple method with high sensitivity and accuracy. The working parameters of instrument, sample processing, the interference and eliminating method of coexisting elements were researched systemically. Cesium, thallium and rhodium were selected as the proper internal standard elements to overcome the non-mass spectrometry interference in the procedure of determination. The results of interference investigation showed that some elements in tailings, such as boron, silicon, calcium, zirconium and aluminum, were likely to cause mass spectrometry interference for the determination of scandium, but the concentration of boron was low(<100 μg·mL-1) in the sample that made it have not noticeable interference in the determination. In addition, smaller mass spectrometry interferences made by aluminum and calcium were negligible under the condition of determination. Most noticeably of all, zirconium and silicon mass interferences were more serious, zirconium would form a double charge (90Zr++) ion to interfere the 45Sc+, actually double-charged ions ionization yield was generally not high enough, the interference would be ignored at low concentration, if higher content of zirconium existed, the equation c′=0.021c(Zr)-0.55 was used to correct results. Moreover, high dissociation energy of silicon-oxygen bond and high related isotopic abundance made silicon oxides (28Si17O+, 29Si16O+) have higher stability, therefore the interference in the Bayan Obo ore tailings at measurement condition was more serious, and the formula c″=0.013c(Si)+0.019 can be used to correct results when silicon was not removed in the pretreatment. In summary, the mass spectrometry interferences to the scandium could be eliminated at determination of tailings. Four different sample pretreatment methods were studied and the result showed that sample determination results were consistent with the standard value and the recoveries of standard sample which were between 97%~99%; the silicon and boron mass spectrometry interferences was effectively overcame when used a mixed acids treatment method which contained Hydrochloric acid, hydrofluoric acid and sulfuric acid, besides it could cut down the measurement fluid salinity therefore so then reduced non-mass spectrometry interference. Standard and actual samples were determined and the results showed that the method, established in this paper to direct determination of scandium of the Bayan Obo metallurgical tailings by ICP-MS, was accurate and the relative standard deviation was less than 5%, and the method detection limit was 0.000 1%.

李建亭, 张翼明, 杜梅, 郝茜, 李建强. ICP-MS法测钪的干扰研究及选冶尾矿中钪的直接测定[J]. 光谱学与光谱分析, 2017, 37(4): 1259. LI Jian-ting, ZHANG Yi-ming, DU Mei, HAO Qian, LI Jian-qiang. Study on the Interferences and Direct Determination of Sc in Metallurgical Tails with Inductively Coupled Plasma Mass Spectrometry[J]. Spectroscopy and Spectral Analysis, 2017, 37(4): 1259.

关于本站 Cookie 的使用提示

中国光学期刊网使用基于 cookie 的技术来更好地为您提供各项服务,点击此处了解我们的隐私策略。 如您需继续使用本网站,请您授权我们使用本地 cookie 来保存部分信息。
全站搜索
您最值得信赖的光电行业旗舰网络服务平台!