采用DZ988N从复杂硫酸盐溶液中高效选择性萃取铜  

Selective and efficient extraction of Cu(II)from a complex sulfate solution containing Co(II),Fe(II),Cu(II),and Zn(II)using DZ988N

作　　者：何静 曹姝琼 陈永明 柳涛 李云 廖方文 代杰 介亚菲 HE Jing;CAO Shu-qiong;CHEN Yong-ming;LIU Tao;LI Yun;LIAO Fang-wen;DAI Jie;JIE Ya-fei(School of Metallurgy and Environment,Central South University,Changsha 410083,China;Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution,Changsha 410083,China)

机构地区：[1]School of Metallurgy and Environment,Central South University,Changsha 410083,China [2]Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution,Changsha 410083,China

出　　处：《Journal of Central South University》2023年第2期454-464,共11页中南大学学报（英文版）

基　　金：Project(2018YFC1902006) supported by the National Key R&D Program of China。

摘　　要：采用鳌合萃取剂DZ988N从含Co(Ⅱ)、Fe(Ⅱ)、Cu(Ⅱ)和Zn(Ⅱ)的硫酸浸出液中分离铜,并对其螯合机理进行了研究。为了优化DZ988N的萃取工艺,通过单因素实验考察了萃取剂浓度(体积比)、水相初始pH值、萃取温度、时间与相比对金属萃取率(ηM)和分离系数(βCu/Co、βCu/Fe和βCu/Zn)的影响,得到DZ988N萃取铜的最优条件为:萃取剂DZ988N浓度25%,水相pH 2.0,萃取温度25℃,时间6min,相比O/A=1/1.5。在此最优条件下,铜的一级萃取率达97.53%,而钴、铁和锌基本不被萃取。此外,采用平衡等温线法确定不同相比下的逆流萃取级数。研究结果表明,当萃取相比为1:1.0,1:1.5和1:2.0时,若使萃余液中铜离子浓度[Cu^(2+)]aq不超过0.005 g/L,所需逆流萃取级数分别为2级、2级和3级。在最优条件下对硫酸浸出液进行2级逆流萃取铜,[Cu2+]aq=0.0044g/L,铜萃取率达99.92%。DZ988N,a kind of chelating extractant,was used to separate copper from the sulfuric acid leaching solution of a polymetallic residue containing Co(II),Fe(II),Cu(II)and Zn(II),and its chelating mechanism was investigated.In order to optimize the DZ988N extraction process,the effects of DZ988N concentration(v/v),pH value of aqueous phase,extraction temperature,time and phase volume ratio(O/A)on metal extraction efficiency(ηM)and separation coefficient(βA/B),were determined in detail.It was found that,under the optimal extraction conditions of DZ988N concentration(v/v)of 25%,pH value of aqueous phase of 2.0,extraction temperature of 25°C,time of 6 min,and phase volume ratio(O/A)of 1/1.5,the single-stage extraction efficiency of Cu(II)was 97.53%,while Fe(II),Co(II)and Zn(II)were basically remained.In addition,extraction isotherms diagram(McCabe-Thiele diagram)was built to determine that a two-stage counter-current extraction is needed.Under the optimal conditions,the copper extraction efficiency was 99.92%and stripped rate was 99.2%.Finally,99.63%Cu was enriched into the stripped solution with 7.85 g/L Cu2+,and 0.38%was lost.

关 键 词：铜萃取 鳌合机理 分离系数 等温线图 

分 类 号：TF811[冶金工程—有色金属冶金]