(1. 昆明理工大學 冶金與能源學院,昆明 650093;
2. 昆明理工恒達科技股份有限公司,昆明 650106;
3. 中國科學院過程與工程研究所,北京 100190)
摘 要: 采用循環(huán)伏安、塔菲爾曲線、陽極極化、交流阻抗測試研究在含不同鋁離子(Al3+)濃度的鋅電解液中極化24 h后的Al/Pb-0.2%Ag(質(zhì)量分數(shù))陽極的腐蝕行為和析氧行為,并通過掃描電鏡和X射線衍射儀分別觀察陽極的表面形貌和陽極氧化膜的物相組成。結(jié)果表明:隨著Al3+濃度的增大,陽極的析氧電位、自腐蝕電流密度以及電極的電荷傳質(zhì)電阻呈現(xiàn)出逐漸增大的趨勢;表觀交換電流密度呈現(xiàn)出逐漸減小的趨勢;α-PbO2(111)衍射峰強度呈現(xiàn)出逐漸減弱的趨勢,Pb(101)衍射峰強度呈現(xiàn)出逐漸增強的趨勢;陽極表面氧化層被腐蝕的程度逐漸加深。Al3+的存在降低了陽極的耐腐蝕性能和導(dǎo)電性能。
關(guān)鍵字: Al/Pb-0.2%Ag陽極;耐腐蝕性能;鋁離子;鋅電積
(1. Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China;
2. Kunming Hendera Science and Technology Co., Ltd., Kunming 650106, China;
3. State Key Laboratory of Multi-Phase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China)
Abstract:The electrochemical properties of Al/Pb-0.2%Ag (mass fraction) alloy anode after 24 h electrolysis in zinc electrolyte containing different Al3+ concentration was investigated. The corrosion behaviors and oxygen evolution of the anode were investigated using cyclic voltammetry, Tafel curves, anodic polarization, and electrochemical impedance spectra. The microscopic morphology and phase composition of the anodic oxide layers were charactered by scanning electron microscopy and X-ray diffraction, respectively. The results show that the increase of Al3+ concentration leads to the increases of oxygen evolution overpotential, corrosion current density and charge-transfer resistance of the anodes while this is contrary to the apparent exchange current density. In addition, the intensity of diffraction peak consisting of α-PbO2(111) exhibits a decreasing trend, which is in contrary of Pb(100) diffraction peak. Furthermore, Al/Pb-0.2%Ag alloy anodes exhibit a less uniform microstructure. The corrosion resistance and electrical conductivity of the anode are decreased when zinc electrolyte containing Al3+.
Key words: Al/Pb-0.2%Ag anode; corrosion resistance; aluminum ion; zinc electrowinning


