电感耦合等离子体原子发射光谱法(ICP-OES)测定含钒尾渣中钒的含量

以氢氟酸、硝酸消解样品,然后加入硫酸络合钛避免其在低酸度介质中水解,并且加热至产生三氧化硫烟以驱赶氢氟酸,以水稀释定容后采用电感耦合等离子体原子发射光谱法（ICP-OES）直接测定含钒尾渣中钒的含量。实验考察了在共存含有铁、钛、铝、铬、锰、钒等元素的含钒尾渣复杂基体中,基体效应、光谱干扰以及背景噪音等影响因素对钒测定的干扰,方法通过优选元素分析谱线、背景校正区域以及光谱仪工作条件,并且采用基体匹配法和同步背景校正法相结合的方式,消除了构成复杂且变化无常的样品基体对测定的影响。结果表明,方法可用于测定0.01%~6.0%的钒,并且样品基体在含20%~40%铁,5%~30%钛时,铝、铬、锰、钠、硅、钙、镁各元素1%~10%的变化对测定无影响,检测下限可达0.0009%;精密度RSD〈3%,加标回收率94%~106%,与高锰酸钾氧化-硫酸亚铁铵滴定化学分析法的测定结果对照一致。

Determination of Vanadium Content in Vanadium Containing Tailing Slags by ICP-OES

The tailing slag sample was firstly digested by hydrofluoric acid and nitric acid. And then sulfuric acid was added to the digestion solution, which resulted in the formation of titanium complex and thus prevented the hydrolysis occurred in a low acidity medium. The solution was further heated to produce sulfur trioxide smoke that could eliminate hydrofluoric acid from the solution. After the solution was diluted with water and went through a predetermined volume test, the content of vanadium in the tailing slag were directly detected by inductively coupled plasma atomic emission spectrometry (ICP-OES). By experiments, the factors that interfere the detection of vanadium in the complicated matrix containing elements such as iron, titanium, aluminum, chromium, manganese, vanadium, etc., were investigated. The interfering factors that were studied included matrix effect, spectral interference and background noise, etc. In addition, the influence of the complicated and volatile sample matrix on the determination was eliminated by conducting several measures, such as proper choice of spectral lines for element analysis, background correction, optimization of spectrometer working parameters, matrix matching and synchronized background correction, etc. The results show that the method can be used for the determination of vanadium in the content range of 0.01% to 6.0% . There are no influences on the determination of vanadium observed when the iron content varies from 20% to 40%, the titanium content varies from 5 to 30%, and the content variations of sodium, aluminum, chromium, manganese, silicon calcium and magnesium are from 1% to 10% in the matrix. The lower limit of detection is 0.000 9%, RSDs are less than 3%, and recovery rates are in the range of 94% to 106%. The results are consistent with those by potassium permanganate oxidation-ammonium ferrous sulfate titration method.