电解分离—电感耦合等离子体发射光谱法测定纯铜中杂质元素

Determination of impurities in pure copper by electrolytic separation-inductively coupled plasma atomic emission spectrometry

以硫硝混酸为电解液,控制电解电流为2 A,建立了电解分离-电感耦合等离子体发射光谱法测定纯铜中19种杂质元素（Mg、Bi、Al、P、Ti、Cr、Mn、Fe、Zn、Co、Ni、As、Se、Zr、Cd、Sn、Sb、Te和Pb）的方法。结果显示,在最佳实验条件下,大于99%的铜沉积至阴极,各杂质元素的回收率大于90%。研究了电解后电解液的酸效应和残余铜对测定的影响,结果表明,基体效应影响较小,可通过基体匹配来进一步消除其影响。各杂质元素的检出限在0.02~4mg/kg之间。运用该方法测定纯铜标准物质GBW02141,各元素测定值与认定值吻合。以高纯铜空白样品做加标回收试验,除Bi外,各元素的加标回收率在90%~100%之间,相对标准偏差（RSD,n=5）在0.2%~7.2%之间。

Through using nitric-sulfuric acid as electrolyte and controlling the electrolytic current at 2 A,nineteen trace impurities（Mg,Bi,Al,P,Ti,Cr,Mn,Fe,Zn,Co,Ni,As,Se,Zr,Cd,Sn,Sb,Te and Pb）in pure copper were determined with a combination of electrochemical deposition separation and inductively coupled plasma atomic emission spectrometry.The results showed that more than 99% of Cu matrix was deposited on cathode with the recoveries of impurities higher than 90 % under the optimized conditions.The effects of acid and residual copper in electrolyte after electrolysis were investigated.It indicated that the matrix effect which was not obvious could be further eliminated by matrix matching.The detection limits of these elements were in the range of 0.02-4 mg/kg.The method has been applied to determine pure copper reference material GBW02141 and the results were consistent with the certified values.The recovery test was conducted with high purity copper as blank.The recoveries of these elements（except Bi） were in the range of 90%-100% with relative standard deviations（RSD,n=5）of 0.2 %-7.2 %.