电感耦合等离子体原子发射光谱法测定硅铁中痕量钛

钛元素含量作为硅铁的一项指标,对其准确、快速测定十分重要。选择硝酸-氢氟酸-高氯酸酸溶体系溶解样品,通过高氯酸冒烟使硅挥发并去除,并在配制钛标准溶液系列时,通过基体匹配法来消除铁基体效应的影响。选择Ti 334.94 nm为分析谱线,采用电感耦合等离子体原子发射光谱法(ICP-AES)测定硅铁中痕量钛。共存元素的干扰试验结果表明:共存元素钙和锰对钛元素的测定无影响。在优化的工作条件下,建立钛元素的校准曲线,校准曲线的线性相关系数r为0.999 8;方法检出限为0.000 54%(质量分数,下同),定量限为0.001 8%。采用实验方法测定硅铁标准样品和硅铁试样中痕量钛,测定结果的相对标准偏差(RSD,n=11)为1.8%~2.7%;标准样品YSB14614-2008和YSBC28605a-2013的测定值和标准值相符合,硅铁试样中钛(wTi=0.005 7%)的加标回收率为99%~104%。

Determination of trace titanium in ferrosilicon by inductively coupled plasma atomic emission spectrometry

The content of titanium is an indicator of ferrosilicon,so the accurate and rapid determination of titanium is very important.The sample was dissolved with nitric acid-hydrofluoric acid-perchloric acid system in experiments. Silicon was removed by volatilization through perchloric acid smoke.Moreover,the influence of matrix effect was eliminated using matrix matching method during the preparation of standard titanium solution series.Ti 334.94 nm was selected as the analysis line.The content of trace titanium in ferrosilicon was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES).The results of interference experiments of coexisting elements showed that calcium and manganese had no influence on the determination of titanium.Under the optimized working parameters, the linear correlation coefficient (r) of calibration curve for titanium was 0.999 8.The limit of detection and the limit of quantification of this method was 0.000 54% (mass fraction,same as below) and 0.001 8%, respectively.The experimental methods were used to determine trace titanium in certified reference materials and actual samples of ferrosilicon.The relative standard deviations (RSD, n=11) of the measured results were between 1.8% and 2.7%.The measured value of certified reference materials (YSB14614-2008 and YSBC28605a-2013) were consistent with the certified value. The spiked recoveries of titanium in ferrosilicon sample (w_Ti=0.005 7%) were between 99% and 104%.