熔融制样-X射线荧光光谱法测定镧铈镨钕稀土合金

样品采用硝酸溶解,加入氨水将待测物沉淀,用无灰滤纸过滤,滤渣经过灼烧后用四硼酸锂和偏硼酸锂混合熔剂熔制成试料片,以波长色散X射线荧光光谱仪进行检测,实现了熔融制样-X射线荧光光谱法测定镧铈镨钕稀土合金中镧、铈、镨、钕的含量。以高纯物质配制校准标样,并分别采用干扰系数法进行谱线重叠干扰校正和可变理论α影响系数法(COAL模式)进行基体效应校正。对方法的精密度和回收率进行考察,相对标准偏差(RSD,n=11)小于2%,回收率介于98%~101%之间。对镧铈镨钕稀土合金实际样品进行分析,测定结果同电感耦合等离子体原子发射光谱法的结果相一致。

Determination of lanthanum-cerium-praseodymium-neodymium rare earth alloy by X-ray fluorescence spectrometry with fusion sample preparation

The sample was dissolved by HNO₃ and added with ammonia to generate precipitates, which was then filtered by ashless filter paper. The residues were burned and fused into test portion slice with mixed flux of Li₂B₄O₇-LiBO₂. The test portion slice were determined by a wavelength dispersive X-ray fluorescence spectrometer. Thus, a determination method for lanthanum, cerium, praseodymium and neodymium in La-Ce-Pr-Nd rare earth alloys was established by X-ray fluorescence spectrometry(XRF)with fusion sample preparation. The calibration sample was prepared by highly pure substance. The spectrum overlapping interference was corrected by interference coefficient method, while the matrix effect was corrected by variable theoretical α influence coefficient method (COAL model). The method precision and recovery was tested. The relative standard deviation (RSD, n=11) was below 2 %. The recoveries were between 98% and 101%. By analyzing the actual sample of La-Ce-Pr-Nd rare earth alloys, it was found the results were consistent with those of inductively coupled plasma atomic emission spectrometry.