电感耦合等离子体质谱法测定硅钢中痕量铝钼钒钛铌

Determination of trace aluminum,molybdenum,vanadium,titanium and niobium in silicon steel by inductively coupled plasma mass spectrometry

研究了应用电感耦合等离子体质谱(ICP-MS)同时测定硅钢中痕量铝、钼、钒、钛、铌元素的分析方法。通过条件试验对测量参数进行了优化,确定RF功率1 400 W,泵速30rpm,采样深度140,雾化压力0.90。样品采用硝酸分解,以Be、Y混合内标校正了测量过程中高基体引起的信号漂移。根据测量时存在的质谱干扰情况,选择同位素27 Al、98 Mo、51 V、47 Ti和93 Nb作为测定同位素,同时通过调节仪器参数使得双电荷离子和氧化物离子的产率最低,以减少其带来的干扰。采用基体匹配法配制校准溶液,以标准加入法建立工作曲线,并扣除试剂空白。该方法各元素的测定下限均可达到1μg/g。用于硅钢标准样品的测定,所得结果与参考值完全吻合,各元素的RSD小于5.2%。

A method for the determination of trace aluminum,molybdenum,vanadium,titanium and niobium in silicon steel by inductively coupled plasma mass spectrometry（ICP-MS） was described.A series of single parameter condition experiment was conducted.The optimized operation parameters with RF power 1 400 W,turbo pump rate 30 rpm,sampling depth 140 and nebulizer pressure 0.90 were obtained.The samples were dissolved by HNO3,and the Be and Y mixing internal standard were used to eliminate the signal drift caused by high matrix concentration.The spectral interferences for all these five elements was also investigated in detail,and the isotopes 27Al,98Mo,51V,47Ti and 93Nb were used for measurement.The yield of double-charge ions and oxide ions were minimized by adjusting instrumental parameters to reduce the mass spectrum interferences.At last,the matrix matched standard solution and the addition method were used to build the calibration curves,and the blank values originated from the reagents were determined and subtracted from the results.The experiment results indicated that for all these five object elements,the LOD of this proposed method were less than 1 μg/g.The method was applied to the determination of some silicon steel CRMs,the results were proved be in good agreement with the certified value,and the RSD for every elements were smaller than 5.2%.