动态反应池-电感耦合等离子体质谱法测定钢铁及合金中硫

Determination of sulfur in iron,steel and alloys by inductively coupled plasma mass spectrometry with dynamic reaction cell

研究了应用动态反应池-电感耦合等离子体质谱法(DRC-ICP-MS)测定钢铁及合金中硫含量的分析方法。针对硫易受多原子离子干扰的特点,采用四极杆质谱仪的动态反应池技术,以O2为反应气,通过测定m/z为48的32S16 O+克服m/z为32的32S+受到的多原子离子干扰,实现了对S的定量分析。研究了仪器的最佳工作条件,基体Fe和共存离子Ca、Ti的干扰效应;选择了合适的分析同位素,采用标准加入法校正了基体的抑制效应。方法检出限为4.0μg/L。将本方法用于实际样品分析,测定值与其它方法结果和标准物质认定值吻合,加标回收率为99%～104%,相对标准偏差均小于6.0%。

A method for the determination of sufur content in iron,steel and alloys by inductively coupled plasma mass spectrometry with dynamic reaction cell（DRC-ICP-MS） has been studied.Since the sulfur was prone to suffer from polyatomic ions interference,the dynamic reaction cell technique of quadrupole mass spectrometer was adopted to overcome the polyatomic ion interference of 32S＋（m/z=32） by measuring the 32S16O＋（m/z=48） with O2 as reaction gas,realizing the quantitative analysis of S.The optimal working conditions of instrument,the interference effect of matrix Fe and coexisting ions（Ca and Ti） were investigated.The appropriate isotopes for determination were selected.The inhibition effect of matrix was corrected by standard addition method.The detection limit of method was 4.0 μg/L.This method has been applied to the determination of actual samples,and the results were consistent with the certified values and those obtained by other methods with recoveries of 99 %-104 % and relative standard deviations（RSD） smaller than 6.0 %.