氧弹燃烧分解-原子荧光光谱法测定铜精矿中汞  

Determination of mercury in copper concentrate by atomic fluorescence spectrometry combined with oxygen bomb combustion decomposition

作　　者：杨春茹 李冀平 冯冬 高建文 米飞 杨欣 YANG Chunru;LI Jiping;FENG Dong;GAO Jianwen;MI Fei;YANG Xin(Qinhuangdao Customs Coal Inspection Technique Center,Qinhuangdao 066003,China)

机构地区：[1]秦皇岛海关煤炭检测技术中心,河北秦皇岛066003

出　　处：《冶金分析》2023年第8期49-54,共6页Metallurgical Analysis

基　　金：石家庄海关科研项目(HE2017K006);海关总署科研项目(2022HK057)。

摘　　要：汞是铜精矿中主要有害元素之一,铜精矿中汞的准确测定具有重要意义。称取0.10 g样品,以0.50 g苯甲酸为助燃剂通过氧弹燃烧法分解样品,挥发逸出的汞被酸性高锰酸钾溶液吸收后用原子荧光光谱法进行测定,建立了氧弹燃烧分解-原子荧光光谱法(AFS)测定铜精矿中汞含量的分析方法。在选定的实验条件下,汞质量浓度在0~2.0 ng/mL范围内与其对应的荧光强度线性良好,相关系数为0.9999。方法检出限为12 ng/g,定量限为40 ng/g。按照实验方法对3个不同汞含量的铜精矿标准物质进行7次平行测定,同时在样品中加入汞标准溶液进行加标回收试验,结果的相对标准偏差(RSD,n=7)为2.1%~5.8%,回收率为90%~107%。选取来自智利、澳大利亚、墨西哥、秘鲁、老挝、西班牙6个地区的铜精矿样品,分别采用实验方法和国家标准GB/T 3884.20—2018中的固体进样直接测汞法进行方法对照,t检验结果表明,这两种方法无统计学意义上的差异。Mercury is one of the main harmful elements in copper concentrate.The accurate determination of mercury in copper concentrate is of great significance.In experiments,0.10 g of sample was decomposed by oxygen bomb combustion using 0.50 g of benzoic acid as the accelerant.The volatilized mercury was absorbed with acid potassium permanganate solution and then determined by atomic fluorescence spectrometry.A method for the determination of mercury content in copper concentrate by oxygen bomb combustion decomposition and atomic fluorescence spectrometry(AFS)was established.Under the selected experimental conditions,the mass concentration of mercury in the range of 0-2.0 ng/mL had good linear relationship with the corresponding fluorescence intensity.The correlation coefficient was 0.9999.The limit of detection of this method was 12 ng/g,and the limit of quantification was 40 ng/g.Three certified reference materials of copper concentrate with different contents of mercury were determined for seven times according to the experimental method.Meanwhile,the standard solution of mercury was added into sample for the standard addition recovery tests.The relative standard deviations(RSD,n=7)of determination results were between 2.1%and 5.8%.The recoveries were between 90%and 107%.Some copper concentrate samples from six regions,i.e.,Chile,Australia,Mexico,Peru,Laos and Spain,were selected and compared respectively by the experimental method and the direct mercury measurement method of solid injection in national standard GB/T 3884.20-2018.The t test results showed that there was no significant statistical difference between the two methods.

关 键 词：铜精矿 汞 氧弹燃烧 原子荧光光谱法(AFS) 

分 类 号：O657.31[理学—分析化学] TF031[理学—化学] TF041[冶金工程—冶金物理化学]