工程科学学报2025，Vol.47Issue(10)：1979-1988,10.DOI:10.13374/j.issn2095-9389.2024.12.26.004
CTAB对Pb-Ag阳极MnO2镀膜电化学性能的影响
Effect of CTAB on the electrochemical performance of MnO2 coatings deposited on Pb-Ag anodes
摘要
Abstract
In industrial zinc electrowinning processes,Pb-Ag alloys(typically containing 0.5%～1.0%Ag(mass fraction))have been widely adopted as inert anodes due to their mechanical durability and cost-effectiveness.However,these anodes exhibit intrinsic limitations in strongly acidic sulfate electrolytes.The low catalytic activity of Pb-Ag alloys toward the oxygen evolution reaction(OER)leads to elevated anode potential and increased energy consumption during zinc production.This high overpotential not only raises power costs but also accelerates the electrochemical corrosion of the Pb-Ag anode.Specifically,lead on the surface undergoes oxidation,resulting in Pb dissolution into the electrolyte.These dissolved lead ions subsequently co-deposit on the cathode,contaminating the zinc product and reducing its purity.Furthermore,the uneven OER activity induces localized current density hotspots,exacerbating structural degradation and shortening anode service life.To address these issues,pre-coating Pb-Ag anodes with MnO2 has emerged as a promising solution.MnO2 coatings effectively enhance the corrosion resistance of Pb-Ag anodes and inhibit surface lead oxidation and dissolution.At the same time,the MnO2 film serves as an excellent catalytic layer,significantly improving the oxygen evolution performance of the electrode.However,the MnO2 film prepared via traditional coating processes often suffer from a loose structure,poor adhesion,and limited protective effects on the Pb-Ag substrate.In the electrodeposition process,additives play a crucial role in optimizing deposit quality,adhesion,and performance while ensuring efficient and consistent electroplating results.Inspired by this,the incorporation of additives is anticipated to improve MnO2 film quality on Pb-Ag anodes.In this study,cetyltrimethyl ammonium bromide(CTAB)was used as an additive to induce the formation of MnO2 films with enhanced corrosion resistance and OER activity by modulating the electrocrystallization process on the Pb-Ag surface.The results demonstrate that introducing appropriate amounts of CTAB into the zinc electrodeposition system accelerates the oxidation of Mn2+to Mn3+intermediates,promotes uniform electrocrystallization of MnO2 on the substrate,and significantly enhances both catalytic activity and corrosion resistance of the electrode.Comparative tests between CTAB-modified anodes(PAM-C)and conventionally coated MnO2 anodes(IPAM)revealed substantial performance improvements.During long-term simulated zinc electrowinning,the CTAB-assisted Pb-Ag/MnO2 anode prepared with 1 g·L-1(PAM-C1)showed superior OER performance and corrosion resistance compared to IPAM.At 500 A·m-2,the oxygen evolution potential of PAM-C1(2.09 V(vs RHE))was 50 mV lower than that of IPAM(2.14 V(vs RHE)),while maintaining stable performance.After 15 days of electrolysis,the lead concentration in the PAM-C1-based system decreased from 0.70 mg·L-1 to 0.61 mg·L-1 compared to the IPAM system.The enhanced performance of the PAM-C1 anode could contribute to more efficient and environmentally friendly zinc production.This work presents a promising approach to reducing energy consumption and improving product quality through additive-regulated MnO2 coating of Pb-Ag anodes,offering valuable insights for the sustainable development of the zinc electrowinning industry.关键词
锌电积/Pb-Ag阳极/MnO2镀膜/添加剂/催化析氧Key words
zinc electrowinning/Pb-Ag anode/MnO2 coating/additive/catalytic oxygen evolution分类
矿业与冶金引用本文复制引用
张泽,王恩泽,郭孟伟,高明远,徐存英,张启波..CTAB对Pb-Ag阳极MnO2镀膜电化学性能的影响[J].工程科学学报,2025,47(10):1979-1988,10.基金项目
云南省重大科技专项资助项目(202302AG050008) （202302AG050008）
云南省中铜应用基础研究企业联合专项资助项目(202401BN070001-021) （202401BN070001-021）
云南省基础研究专项资助项目(202401CF070150) （202401CF070150）
昆明理工大学"双一流"创建联合专项面上资助项目(202301BE070001-063) （202301BE070001-063）
