微分脉冲溶出伏安法测定锌电解液中铜铅镉镍  

Determination of copper,lead,cadmium and nickel in zinc electrolyte by differential pulse stripping voltammetry

作　　者：慕鹏涛 沈庆峰[2] 俞小花[2] 徐双全[2] 刘春侠[1] 

机构地区：[1]昆明理工大学分析测试研究中心,云南昆明650093 [2]昆明理工大学冶金与能源工程学院,云南昆明650093

出　　处：《冶金分析》2016年第10期15-20,共6页Metallurgical Analysis

基　　金：国家自然科学基金青年基金(51304094)

摘　　要：采用微分脉冲溶出伏安法,建立了氨水-氯化铵体系中,氨水掩蔽Zn^(2+),丁二酮肟(DMG)络合Ni^(2+),不经预分离测定痕量的Cu^(2+)、Pb^(2+)、Cd^(2+)和Ni^(2+)的方法。本体系可消除大量Zn^(2+)对Ni^(2+)、Cd^(2+)的干扰。在起始电位―0.80V、终止电位―0.1V、富集电位―0.85V、富集时间100s、扫描速率0.015V/s、加入0.5mL氨水-氯化铵溶液的条件下,Cu^(2+)、Pb^(2+)、Cd^(2+)的溶出峰电位分别为―0.28、―0.47、―0.63V,质量浓度分别在2.0×10^(-6)~1.0×10^(-3)、1.6×10^(-6)~6.6×10^(-3)、2.3×10^(-6)~1.1×10^(-2) g/L范围内与其峰电流呈良好的线性关系,方法检出限分别为8.9×10^(―8)、8.1×10^(―7)、2.1×10^(―7) g/L。不更换溶液,再向溶液中加入0.5mL DMG溶液、0.6mL氨水,在起始电位―0.90V、终止电位―1.2V、富集电位―0.80V、富集时间40s、扫描速率0.015V/s的条件下,Ni^(2+)的溶出峰电位为―1.03V,质量浓度在1.0×10^(―6)~5.6×10^(―4) g/L范围内与其峰电流呈良好的线性关系,方法检出限为4.6×10^(―7)g/L。溶液中可能存在的常见离子不干扰Cu^(2+)、Pb^(2+)、Cd^(2+)和Ni^(2+)的测定。采用标准加入法测定混合标准溶液中的Cu^(2+)、Pb^(2+)、Cd^(2+)和Ni^(2+),其结果的相对标准偏差(RSD,n=6)为0.075%~1.8%;回收率为90%~109%。方法可用于硫酸锌电解液、中性上清液等实际样品的测定,其中中性上清液的测定结果与电感耦合等离子体原子发射光谱法(ICP-AES)测定结果基本吻合。The determination method of trace Cu^（2＋）,Pb^（2＋）,Cd^（2＋）and Ni^（2＋）by differential pulse stripping voltammetry without pre-separation was established.In ammonia water-ammonium chloride system,Zn^（2＋）was masked by ammonia water,and Ni^（2＋）was complexed by dimethylglyoxime（DMG）.This system could eliminate the interference of much Zn^（2＋）to the determination of Ni^（2＋）and Cd^（2＋）.The stripping peak potential for Cu^（2＋）,Pb^（2＋）and Cd^（2＋）was-0.28,-0.47and-0.63 V,respectively,under the following experimental conditions：the initial potential was-0.80 V,the terminal potential was-0.1V,the accumulation potential was-0.85 V,the accumulation time was 100 s,the scanning rate was 0.015V/s,and 0.5mL of ammonia water-ammonium chloride solution was added.The mass concentration in range of 2.0×10^（-6）-1.0×10^（-3）,1.6×10^（-6）-6.6×10^（-3） and 2.3×10^（-6）-1.1×10^（-2） g/L for Cu^（2＋）,Pb^（2＋）and Cd^（2＋）showed good linear relationship to the peak current.The detection limit was 8.9×10^（―8）,8.1×10^（―7） and2.1×10^（―7） g/L,respectively.If the solution was not replaced,and 0.5mL of DMG and 0.6mL of ammonia water were added into solution,the stripping peak potential for Ni^（2＋）was-1.03 Vunder the following conditions：the initial potential was-0.90 V,the terminal potential was-1.2V,the accumulation potential was-0.80 V,the accumulation time was 40 sand the scanning rate was 0.015V/s.The mass concentration of Ni^（2＋）in range of 1.0×10^（―6）-5.6×10^（―4） g/L showed good linear relationship to the peak current.The detection limit of method was 4.6×10-7 g/L.The common ions in solution did not interfere with the determination of Cu^（2＋）,Pb^（2＋）,Cd^（2＋）and Ni^（2＋）.The content of Cu^（2＋）,Pb^（2＋）,Cd^（2＋）and Ni^（2＋）in mixed standard solution was determined by standard addition method.The relative standard deviations（RSD,n=6）w

关 键 词：微分脉冲溶出伏安法 铜 銘 福 樣 辞电解液 

分 类 号：TF813[冶金工程—有色金属冶金] O657.1[理学—分析化学]