电感耦合等离子体质谱法测定地球化学样品中痕量铑的干扰消除方法探讨  

Discussion on elimination of interference in determination of trace rhodium in geochemical sample by inductively coupled plasma mass spectrometry

作　　者：于亚辉[1] 王琳[1] 王明军[2] 胡家祯[1] 陈浩凤[1] 程祎[1] 

机构地区：[1]河南省岩石矿物测试中心,国土资源部贵金属分析技术重点实验室,河南郑州450012 [2]河南省地质矿产勘查开发局第一地质勘查院,河南南阳473003

出　　处：《冶金分析》2017年第9期25-32,共8页Metallurgical Analysis

基　　金：河南省“两权价款”地质科研项目(豫国土资发[2016]56号-4)

摘　　要：采用电感耦合等离子体质谱法(ICP-MS)测定地球化学样品中痕量Rh时,待测溶液的基体及分子离子干扰严重影响ICP-MS测定^(103)Rh的准确性。实验以10ng/mL的^(175)Lu消除基体干扰,以数学校正方程消除多原子离子^(87)Sr^(16)O^+、^(63)Cu^(40)Ar^+、^(86)SrOH、^(206)Pb^(2+)对^(103)Rh的干扰,最终实现了电感耦合等离子体质谱法测定地球化学样品中痕量Rh。分别详细考察了Cu、Sr、Pb对Rh测定的干扰情况,不仅有效消除了^(87)Sr^(16)O^+、^(63)Cu^(40)Ar^+、^(86)SrOH多原子离子对^(103)Rh的测定干扰,而且发现了双电荷离子^(206)Pb^(2+)对^(103)Rh的测定存在严重的质谱干扰。同时通过向不同浓度Rh的标准溶液中分别加入不同量的干扰元素Cu、Sr及Pb进行试验,得到了对^(103)Rh元素进行校正的数学校正方程。实验表明,Rh在0.050~100.0ng/mL范围内与其对应的信号强度呈良好的线性关系,线性相关系数为0.999 9,方法检出限(3σ)为0.014ng/g。采用实验方法对铂族元素地球化学一级标准物质中Rh进行分析,结果与认定值的相对误差(RE)为-7.27%~6.15%,相对标准偏差(RSD,n=12)均不大于8.6%。将实验方法应用于云南、四川、新疆等地区不同含量贵金属地球化学样品中Rh的测定,所得结果与锡试金方法符合性较好。During the determination of trace rhodium in geochemical samples by inductively coupled plasma mass spectrometry（ICP-MS）,the determination accuracy of ^（103）Rh was severely affected by the interference of matrix and molecule ions in testing solution.The matrix interference was eliminated with 10ng/mL ^（175）Lu as internal standard.The interference of multi-atomic ions such as ^（87）Sr^（16）O~＋,^（63）Cu^（40）Ar~＋,^（86）SrOH and ^（206）Pb^（2＋）with the determination of ^（103）Rh was eliminated by mathematical correction equation.Consequently,a determination of trace rhodium in geochemical samples by ICP-MS was realized.The interference of Cu,Sr and Pb with the determination of Rh was investigated in detail.The interference of^（87）Sr^（16）O~＋,^（63）Cu^（40）Ar~＋and ^（86）SrOH with the determination of ^（103）Rh was effectively eliminated.Moreover,it was found that the double-charge ion of ^（206）Pb^（2＋）had serious mass spectrometry interference with the determination of Rh.Meanwhile,various amounts of interference elements（Cu,Sr and Pb）were added into the standard solution of Rh with different concentrations for test.The mathematical correction equation for（103）Rh was obtained.The experimental results indicated that the concentration of Rh in range of 0.050-100.0ng/mL had good linear relationship to its corresponding signal strength with correlation coefficient of 0.999 9.The detection limit of method（3σ）was 0.014ng/g.The proposed method was applied to the analysis of Rh in primary reference material of geochemical sample of platinum family element.The relative errors（RE）between the found results and certified values were between-7.27% and 6.15%.The relative standard deviations（RSD,n=12）were all not more than 8.6%.The experimental method was used for the determination of Rh in geochemical samples with various precious metal content from Yunnan,Sichuan and Xinjiang,and the results were consistent with those obtained by tin as

关 键 词：高压密闭消解 电感耦合等离子体质谱法 地球化学样品 铑 质谱干扰 数学校正方程 

分 类 号：O657.63[理学—分析化学]