硫脲络合–火焰原子吸收光谱法测定古炉渣中的银、镉、钴、镍

Determination of silver, cadmium, cobalt and nickel content in ancient furnace slag by thiourea complexation–flame atomic absorption spectrometry

建立硫脲络合–火焰原子吸收光谱法测定古炉渣中的银、镉、钴、镍。样品采用盐酸–硝酸–氢氟酸–高氯酸四酸体系溶解并蒸发至白烟冒尽,用体积分数10%的盐酸溶液溶解残渣至溶液清亮,加入10 mL 50 g/L硫脲溶液进行络合,定容于100 mL容量瓶中,混匀澄清后直接测定溶液中的银、镉、钴、镍。试验优化了灯电流、狭缝、乙炔流量和燃烧器高度等仪器工作条件,探讨了试样溶液的酸度、络合剂硫脲的浓度、共存元素对测定结果的影响。各元素校准曲线的线性相关系数均大于0.999 0,检出限为0.018～0.031μg/mL,加标回收率为97%～103%,样品测定结果的相对标准偏差为0.7%～1.8%(n=9)。该方法简便快捷,易于掌握,适合古炉渣样品的快速测定。

Silver,cadmium,cobalt and nickel in ancient furnace slag were determined by thiourea complexation-flame atomic absorption spectrmetry.The sample was treated with hydrochloric acid-nitric acid-hydrofluoric acid-perchloric acid system,dissolved and evaporated to remove all white smoke.The residue was dissolved to clear solution by hydrochloric acid solution with the volume fraction of 10%,10mL 50g/L thiourea solution was added in for complexation,and formed constant volume in 100mL capacity bottle.After mixing and clarification,the content of silver,cadmium,cobalt and nickel in the solution were determined directly.The working conditions of the instrument were optimized such as lamp current,slit,acetylene flow and burner height.The interference of the test solution acidity,the concentration of thiourea and the coexisting elements on the determination were discussed.The linear correlation coefficients of the calibration curves of each element were all more than 0.9990,the detection limits were 0.018-0.031μg/mL,the recoveries of standard addition were 97%-103%,and the relative standard deviations of sample determination results were 0.7%-1.8%(n=9).The method is simple,quick and easy to master,it is suitable for the rapid determination of the ancient furnace slag sample.