电感耦合等离子体原子发射光谱法测定钢中铌钨锆

采用硫酸和硝酸溶解样品,加入草酸铵溶液以溶解试样处理中形成的盐类和防止试液中铌、钨和锆水解,在优化仪器工作参数条件下用电感耦合等离子体原子发射光谱法(ICP-AES)测定试液中铌、钨、锆含量,从而建立了钢中铌、钨和锆的测定方法。研究表明:通过加热,0.1 g钢样能溶解于15 mL硫酸(1+4)和几滴硝酸中,且冒硫酸烟后出现的盐类,加入10 mL 4.0 g/L草酸铵溶液可将其溶解完全。以Nb 316.340 nm,Zr 343.823 nm,W 207.011 nm为分析谱线,采用基体匹配方法克服基体干扰。待测元素校准曲线相关系数大于0.999 5,铌、钨和锆的检出限分别为 1.9、9.9 和 3.2 ng/mL。方法应用于YSBC11217-94低合金钢标准样品中铌、钨和锆的测定,结果与认定值相符,相对标准偏差(n=10)分别为1.7%,1.1%和2.1%,加标回收率在97%～104%之间。对其他标准样品(合金钢、合金结构钢、低合金钢)及合成钢样品中铌、钨、锆进行测定,测定值与认定值或参考值相符。

Determination of niobium,tungsten and zirconium in steel by inductively coupled plasma atomic emission spectrometry

The sample was dissolved with sulfuric acid and nitric acid. The ammonium nitrate solution was added into sample solution to dissolve the salts formed in treatment process and to prevent the hydrolysis of niobium, tungsten and zirconium. Under the optimized instrumental operation conditions, the content of niobium, tungsten and zirconium in sample solution was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Consequently, the determination method of niobium, tungsten and zirconium in steel was established. The researches indicated that 0.1 g of steel sample could be dissolved in 15 mL of sulfuric acid and several drops of nitric acid by heating and the salts formed after fumes of sulfuric acid to be evolved could be completely dissolved by adding 10 mL of 4.0 g/L ammonium nitrate solution. Nb 316.340 nm, Zr 343.823 nm and W 207.011 nm were selected as the analysis lines. The matrix interference was eliminated by matrix matching method. The correlation coefficients of calibration curves of testing elements were all higher than 0.999 5. The detection limits of niobium, tungsten and zirconium were 1.9, 9.9 and 3.2 ng/mL, respectively. The proposed method was applied to the determination of niobium, tungsten and zirconium in YSBC11217-94 low alloy steel standard sample. The found results were consistent with the certified values. The relative standard deviation (RSD, n=10) was 1.7%, 1.1% and 2.1%, respectively. The recoveries of standard addition were between 97% and 104%. The content of niobium, tungsten and zirconium in other standard samples (including middle alloy steel, structural alloy steel and low alloy steel) and synthetic steel samples was determined. The found results were consistent with the certified values or reference values.