论文部分内容阅读
目的:建立测定水中铅的新反应体系的氢化物发生原子荧光法。方法:在酸性介质中,以铁氰化钾为氧化剂,草酸和焦磷酸钠为掩蔽剂,1%盐酸溶液为载流,先将样品中Pb~(2+)氧化为Pb~(4+),Pb~(4+)与硼氢化钾反应生成挥发性铅的氢化物PbH_4,将氢化物导入原子化器,检测其荧光强度值。结果:方法的标准曲线最佳线性范围:0~50μg/L,相关系数为0.9999。方法检出限0.17μg/L,最低检出浓度为0.51μg/L,相对标准偏差1.4%~4.0%,回收率为95.7%~104.0%。对2个标准参考物质的分析结果令人满意。结论:用该法测定水中铅,特点是操作简便、线性关系好、检出限低、重复性好、回收率高。对样品的测定结果与国标法一致,测定结果之间无显著性差异,能用于水中铅的准确测定。
Objective: To establish a new hydride generation atomic fluorescence spectrometry method for the determination of lead in water. Methods: Pb2 + was first oxidized to Pb4 + in the acidic medium with potassium ferricyanide as oxidant, oxalic acid and sodium pyrophosphate as masking agent and 1% hydrochloric acid as carrier. , Pb ~ (4+) reacts with potassium borohydride to form PbH_4, a lead hydride. The hydride is introduced into the atomizer to detect its fluorescence intensity. Results: The best linearity of the standard curve was 0 ~ 50μg / L with a correlation coefficient of 0.9999. The detection limit was 0.17μg / L, the lowest detection limit was 0.51μg / L, the relative standard deviation was 1.4% ~ 4.0% and the recovery was 95.7% ~ 104.0%. The results of two standard reference materials were satisfactory. Conclusion: The method for the determination of lead in water is characterized by simple operation, good linearity, low detection limit, good repeatability and high recovery rate. The results of the determination of the sample with the national standard method, the determination of no significant difference between the results can be used for accurate determination of lead in water.