电感耦合等离子体原子发射光谱法测定萤石中硅铝铁钾镁钛

样品采用氢氧化钠在锆坩埚中熔融后、再使用硼酸溶液浸取和硝酸酸化,使用电感耦合等离子体原子发射光谱法(ICP-AES)测定硅、铝、铁、钾、镁、钛,从而建立了萤石中硅、铝、铁、钾、镁、钛的测定方法。试验探讨了基体效应的影响,认为溶液中大量存在的钠(4.37~4.83mg/mL)对钾的信号强度稍有影响,但其影响程度小于2.4%,而对其他元素的影响可以忽略;钙(120~200μg/mL)、硼(56.8~85.2μg/mL)和锆(小于4.0μg/mL)对各元素的测定没有显著的影响。试验还考察了酸度的影响,结果表明溶液中一定酸度范围的硝酸对各元素的测定基本没有影响。在选定的工作条件下,各元素的校准曲线呈线性,线性相关系数r为0.999 9~1.000 0,方法检出限为3~105μg/g。方法的测定范围能覆盖所有萤石牌号中硅、铝、铁、钾、镁、钛等元素的测定。按照实验方法测定萤石标准样品YSB 14791-02、GBW07252、GSB 08-1348-2001、Fluorspar 2712中硅、铝、铁、钾、镁、钛,结果的相对标准偏差(RSD,n=5)为0.10%~9.5%,并与认定值相吻合。

Determination of silicon,aluminum, iron,potassium, magnesium and titanium in fluorspar by inductively coupled plasma atomic emission spectrometry

The fluorspar sample was fused with sodium hydroxide in zirconium crucible followed by leaching with boric acid solution and acidification with nitric acid. The content of silicon, aluminum, iron, potassium, magnesium and titanium in fluorspar was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). The determination method of silicon, aluminum, iron, potassium, magnesium and titanium in fluorspar was established. The influence of matrix effect was discussed. It was found that the signal intensity of potassium was slightly affected by much sodium in solution (4.37-4.83 mg/mL), but the error was less than 2.4%. Meanwhile, its influence on other elements could be negligible. Calcium (120-200 μg/mL), boron (56.8-85.2 μg/mL) and zirconium (<4 μg/mL) had no significant influence on the determination of elements. The effect of acidity was also investigated in experiments. The results indicated that the effect of acidity in certain range could be ignored. The calibration curves of elements were linear under the working conditions with correlation coefficients of r=0.999 9-1.000 0. The detection limits of method were between 3 μg/g and 105 μg/g. The determination range could cover the content range of silicon, aluminum, iron, potassium, magnesium and titanium in all fluorspar samples. The content of silicon, aluminum, iron, potassium, magnesium and titanium in certified reference materials including YSB 14791-02, GBW07252, GSB 08-1348-2001 and Fluorspar 2712 was analyzed according to the experimental method. The found results were consistent with the certified values. The relative standard deviations (RSD, n=5) were between 0.10% and 9.5%.