固体进样直接测定法测定铜精矿中汞

建立了固体进样直接测定法测定铜精矿中汞含量的方法。铜精矿样品在测汞仪的分解炉中经300℃干燥和750℃高温热分解后,汞被催化分解为汞原子,于850℃齐化成金汞齐。汞蒸气被氧气流带入单波长光学吸收池,在波长253.7 nm处测量汞的吸光度,采用标准曲线法计算汞量。方法的线性范围分别为0~1.00,0~100μg/mL,线性相关系数为0.9999,检出限分别为0.10,0.04 ng/g。5个汞含量不同的铜精矿样品测定结果的相对标准偏差为2.14%~4.35%(n=11),样品加标回收率为92.00%~104.02%。采用该方法分别对2个铜精矿样品和铜精矿国际标准物质进行测定,测定结果与标准分析方法测定值和标准物质标示值基本一致。该方法简便、快速、准确,可以作为标准方法推广使用。

Determination of mercury in copper concentrate by solid sampling and direct mercury analysis method

The direct determination method of mercury content in copper concentrate by solid sample introduction was established.After the copper concentrate sample was dried at 300℃and thermally decomposed at 750℃in the decomposition furnace of the mercury meter,mercury was catalytically decomposed into mercury atoms,which were homogenized into gold amalgam at 850℃.Mercury vapor was introduced into a single wavelength optical absorption cell by oxygen flow,and the absorbance of mercury was measured at 253.7 nm.The mercury content was calculated by standard curve method.The linear ranges of the method were 0-1.0,0-100μg/mL,respectively,the linear correlation coefficients were all 0.9999,and the detection limits were 0.10,0.04 ng/g,respectively.The relative standard deviations of the determination results of five copper concentrate samples with different mercury contents were 2.14%-4.35%(n=11),and the recovery rate of the samples were 92.00%-104.02%.The method was used to determine two copper concentrate samples and the international standard substance of copper concentrate,respectively.The determination results were basically consistent with the determination results of the standard analysis method and the standard value of the standard substance.The method is simple,rapid and accurate,it can be used as a standard method.