微波消解-电感耦合等离子体原子发射光谱法测定高碳铬铁中硅磷

以氢氟酸、高氯酸为溶剂,采用微波消解法处理高碳铬铁样品,电感耦合等离子体原子发射光谱仪测定溶液中的硅和磷。实验优化了电感耦合等离子体原子发射光谱仪的工作条件,选择251.612 nm和213.618 nm谱线分别作为硅、磷的分析线。探讨了基体元素铁、铬和溶样酸干扰及校正。结果表明,铁和铬对测定影响不大,采用基体匹配法可消除其干扰;溶样酸的干扰可通过控制样品和校准曲线样品的溶样酸一致来减小或消除。硅和磷的检出限分别为0.001 5%和0.002 1%。对高碳铬铁标准样品和实际样品进行分析,结果同认定值或其他方法(碱熔—ICP-AES法、XRF法)的测定值相一致,相对标准偏差为0.40%~5.3%(n=11)。

Determination of silicon and phosphorus in high carbon-chrome iron by inductively coupled plasma atomic emission spectrometry after microwave digestion

The high carbon-chrome iron sample was treated by microwave digestion with hydrofluoric acid and perchloric acid as solvent. The content of silicon and phosphorus was then determined by inductively coupled plasma atomic emission spectrometry. The working conditions of inductively coupled plasma atomic emission spectrometer were optimized. In this study, 251. 612 nm and 213. 618 nm were used as the analytical lines of silicon and phosphorus, respectively. The interference and correction of matrix iron, chrome and acids were discussed. The results indicated that iron and chrome had little interference with the determination, which could be eliminated by matrix matching method. The interference of acid could be reduced or eliminated by adding the same amount of acid into sample and standard sample. The detection limits of silicon and phosphorus were 0. 0015 % and 0. 002 1%, re-spectively. The standard sample and actual sample of high carbon-chrome iron were analyzed by this method. The results were consistent with the certified values or those obtained by other methods (alkali fusion ICP-AES method, XRF method). The relative standard deviations (RSD) were in the range of 0.40 %-5.3 % (n=11).