摘要
采用不同沉淀剂(HCl和KSCN)分离银基体,研究沉淀方式对纯银中有害元素As和Hg的电感耦合等离子体发射光谱(ICP-AES)测定回收率的影响。结果表明,两种沉淀方式均不吸附As,但对Hg均有吸附,其原因是Hg与沉淀发生共沉淀;采用沉淀剂滴加-搅拌的方式,AgCl沉淀仍然吸附Hg,但可避免AgSCN对Hg的吸附;Hg测定加标回收率大于95%,相对标准偏差(RSD)小于5%,可满足杂质元素Hg测定要求。对吸附机理的探讨认为,由于AgCl沉淀密度较大、致密度高,与HgCl2可能形成共晶,因而难以通过慢沉淀-搅拌的方式消除对Hg的共沉淀吸附。
The silver matrix was separated by HCl and KSCN precipitants,and the effect of precipitation methods on the recovery rates of harmful elements As and Hg in pure silver tested by ICP-AES was studied.The results show that the element As was not adsorbed by AgCl and AgSCN precipitations,and that the element Hg was adsorbed by coprecipitation for the two separation methods.The drip-stirring method can avoid the absorption of Hg by AgSCN precipitation,while there is still Hg adsorption for AgCl precipitation.The adsorption of Hg by AgCl precipitation is attributed to the formation of eutectic with HgCl2 due to its larger sediment density and higher density,so it is difficult to eliminate the coprecipitation adsorption of Hg by slow precipitation and stirring.The recovery rate of Hg is above 95%,and the relative standard deviation is less than 5%,and the results meet the measurement requirements of the impurity element Hg.
作者
李桂华
胡家琨
刘雪松
黄准
赵潇雪
张瑞峰
LI Guihua;HU Jiakun;LIU Xuesong;HUANG Zhun;ZHAO Xiaoxue;ZHANG Ruifeng(National Gold&Diamond Testing Center,Jinan 250014,China;Shandong Provincial Key Laboratory of Metrology and Measurement,Shandong Institute of Metrology,Jinan 250014,China;Qingdao Product Quality Supervision and Testing Research Center,Qingdao 266101,Shangdong,China)
出处
《贵金属》
CAS
CSCD
北大核心
2018年第4期65-69,共5页
Precious Metals
基金
山东省质监系统科技计划项目(2017KY12Z00
2016KY05)
