CuCl_2-NaCl溶液中铜氯络合物浓度的线性扫描伏安法分析  

Linear sweep voltammetry for analysis of the concentration of copper chloride complex in CuCl_2-NaCl solution

作　　者：张艳清[1,2] 李和平[1] 刘庆友[1] 徐丽萍[1] 张磊[3] 

机构地区：[1]中国科学院地球化学研究所地球深部物质与流体作用地球化学研究室,贵州贵阳550002 [2]中国科学院研究生院,北京100049 [3]安徽省地质测绘技术院,安徽合肥230022

出　　处：《冶金分析》2011年第5期1-6,共6页Metallurgical Analysis

基　　金：中国科学院大型设备研制项目(YZ200720);国家自然科学基金项目(40573046)资助

摘　　要：在常压和室温下,对添加与不添加NaCl的CuCl2溶液进行了线性扫描伏安法研究,得到了在0～-0.8 V(相对开路电势)电势区间的伏安曲线。对比两种溶液在扫描速率为5mV/s时的曲线,发现添加NaCl后Cu2+与Cl-形成了参与电化学反应的络合物[CuCl3]-,且伏安曲线发生了以下变化:第1个峰的峰电位变正,第2个峰的峰电流大大降低,两个峰的峰电位差变大。以不同的扫描速率进行电势扫描,体系所表现的可逆性也不一样。扫描速率大于10 mV/s时体系不可逆,扫描速率在1～10 mV/s的范围时第一步电极反应的可逆性良好。当体系处于可逆区时,根据峰电流值和扫描速率之间的关系,计算得到了在电极上发生反应的络合物[CuCl3]-初始浓度为2.97×10-3mol/L。本工作的研究思路和技术路线可望对未来湿法冶金、地质和地球化学等领域中溶解态金属络合物的电化学分析具有重要的借鉴作用。The linear sweep voltammetry of copper chloride solution with and without NaCl was studied at room temperature and atmospheric pressure.The voltammetry curves in potential interval of 0-0.8 V（vs.OCP） were obtained.By comparing the curves of two solutions with scanning rate of 5 mV/s,it was found that Cu2＋ reacted with Cl-after adding NaCl to form the complex -which participated in electrochemical reaction.Moreover,the voltammetry curves showed changes as follows： the peak potential of the first peak moved toward positive direction,the peak current of the second peak decreased remarkably,and the peak potential difference of two peaks broadened.When the potential was scanned with different rates,the showed reversibility of system was also different： the system was irreversible when the scanning rate was higher than 10 mV/s,while the reversibility of first electrode reaction was good in the range of 1-10 mV/s.In the reversible region of system,the initial concentration of complex -on electrode be calculated as 2.97×10-3 mol/L based on the relationship between peak current and scanning rate.The research idea and technical route of this study had important reference significance for electrochemical analysis of dissolved metal complex in the fields of hydro-metallurgy,geology and geochemistry in future.

关 键 词：CuCl2-NaCl溶液 线性扫描伏安法 铜氯络合物 浓度 

分 类 号：O657.14[理学—分析化学] TF113[理学—化学]