密闭微波消解-测汞仪测定铜精矿中高含量的汞

Determination of High Content of Mercury in Copper Concentrate by Mercury Analysis Method with Closed Microwave Digestion

建立了微波消解-测汞仪测定铜精矿中高含量汞的分析方法。采用在密闭的环境下微波消解铜精矿试样,既能保证试样溶解完全,又有效地避免了高温溶样对易挥发元素汞的损失。将铜精矿试样进行微波消解处理后,将试液移取至石英舟中,试液在分解炉中经历干燥和高温热分解后,试液中的汞被还原成汞原子,再被氧气流带进汞齐化管中进行汞齐化反应,汞被选择性吸附,于900℃加热释放出汞蒸气,汞蒸气被氧气流带入单波长光学吸收池进行原子吸收光谱测定,测定结果的相对标准偏差为0.62%~2.0%(n=11),加标回收率为98.5%~100%,测定范围为0.60~1000μg/g,可测定汞含量较高的铜精矿,且有效地延长了仪器的使用寿命。方法操作简单、快速稳定、重现性良好,适合于铜精矿中高含量汞的测定。

An analytical method for the determination of high mercury content in copper concentrate with microwave digestion and mercury measuring instrument was established.Microwave digestion of copper concentrate samples under closed environment can not only ensure the complete dissolution of samples,but also effectively avoid the loss of volatile element mercury by high temperature dissolution.After microwave digestion of copper concentrate samples,the test solution is moved to a quartz boat.After the test solution goes through drying and high temperature thermal decomposition in a decomposed furnace,the mercury in the test solution is reduced to mercury atoms,and then taken into the amalgamation tube by oxygen flow for amalgamation reaction.The mercury is selectively adsorbed and the mercury vapor is released after heating at 900℃.The mercury vapour was brought into the single-wavelength optical absorption cell by oxygen flow for atomic absorption spectrometry determination.The relative standard deviation of the determination results was 0.62%-2.0%(n=11),the standard recovery was 98.5%-100%,and the determination range was 0.60-1000μg/g.Copper concentrate with high mercury content could be determined.And the service life of the instrument is extended effectively.The method is simple,rapid,stable and reproducible.It is suitable for the determination of high mercury content in copper concentrate.