【摘要】 本文将造纸黑液中的木质素磺酸钠经脱磺提纯制得纯化木质素（Lignin），并通过粉末冶金技术制备出铅-木质素（Pb-Lignin）复合阳极。利用场发射扫描电镜（FESEM）、傅里叶红外光谱（FTIR）、核磁共振波谱（NMR）、电子探针显微分析（EPMA）、腐蚀失重实验以及电化学测试研究了Lignin对铅基阳极的电化学及耐腐蚀性能的影响。结果表明：Lignin为球形结构，具有丰富的含氧活性官能团，是一种电化学反应活性高、稳定性强的优良电极活性材料。掺杂Lignin可不同程度地改善铅基阳极的电化学性能：在模拟锌电积条件下，当Lignin掺杂量为0.8%时，对铅基复合阳极改性效果最好，此时Pb-0.8%Lignin复合阳极较纯铅阳极和Pb-Ag-Ca复合阳极的伏安电荷量分别高出1.25和1.23倍，双电层电容C_dl分别高出1.94和1.50倍，表观交换电流密度j₀均高出一个数量级；在500 A·m^-2的电流密度下，其析氧稳态电位为1.528 V，较纯铅电极降低125 mV，腐蚀速率降低了31.6%，表现出优异的析氧催化活性和耐腐蚀性能。更多还原

【Abstract】 Zinc metal has an active chemistry and is widely used in industries such as galvanised protective film and battery manufacturing. Eighty-five percent of zinc metal is produced by hydrometallurgy. Zinc electrowinning, as a vital part of hydrometallurgy, accounts for 80% of the total energy consumption of the hydrometallurgical process. During the electrowinning of zinc, the anodic oxygen evolution reaction has a high charge transfer energy barrier, which results in the anode generating a large overpotential of oxygen evolution potential. This leads to an increase in tank voltage and energy consumption. Concurrently, the anode material must be used in an environment with high acidity, high oxidation, high current density, and the co-existence of halogen ions. This results in corrosion of the anodes, which consequently reduces their service life. The anode sludge also has an impact on the quality of the zinc cathode. Currently, lead-based anodes are predominant in the wet zinc refining industry. However, lead-based anodes still have problems with high oxygen evolution potential and poor corrosion resistance. Lead-based anodes can be modified by doping functional metal elements. For instance, the incorporation of silver, a noble metal with electrocatalytic properties, can diminish the oxygen evolution potential of lead-based anodes. Nevertheless, silver is unable to enhance the mechanical strength of lead-based anodes, and the introduction of the precious metal silver will also considerably elevate the production cost of the anodes. It is therefore of great significance to identify a renewable and low-cost reinforcing phase that can be used as an effective substitute for silver in order to enhance the oxygen precipitation catalytic activity and corrosion resistance of conventional lead-based anodes. In this study, the sodium lignosulfonate, a byproduct of the paper industry, was employed as the primary raw material. The purified lignin was obtained following desulfurisation and purification. PbLignin composite anodes were prepared by incorporating lignin into Pb-based anodes through the use of powder metallurgy technology. The impact of lignin on the electrochemical performance and corrosion resistance of Pb-x Lignin composite anodes（x=0, 0.2, 0.4, 0.6, 0.8, 1.0, %, mass fraction） was investigated. The prepared lignin was micron-sized spherical, with the benzene ring structure preserved intact. Lignin is rich in oxygen-containing active functional groups and is an excellent electrode active material with high electrochemical reactivity and stability. The doped lignin exhibited a varying degree of modification effect on the lead-based anode. The enhancement of the electrochemical performance and corrosion resistance of the lead-based composite anode by lignin exhibited an initial increase and subsequent decrease with increasing lignin doping under simulated zinc electrowinning conditions. This phenomenon could be attributed to the structural composition of the prepared lignin, which comprised lilac-based and p-hydroxyphenyl structural units, rendering it more prone to accelerate the oxygen precipitation electrocatalytic reaction on the anode surface. When the doping amount exceeded 0.8%, π-π interactions and hydrogen bonding between lignin molecules led to severe agglomeration, resulting in an uneven distribution of lignin on the surface of the lead anode and a weakening of the enhancement effect on the lead-based anode. The optimal modification of the leadbased composite anode was achieved when the doping amount of lignin was 0.8%. At this juncture, the Pb-0.8%Lignin composite anode exhibited a 1.25 and 1.23-fold increase in voltammetric charge, a 1.94 and 1.50-fold enhancement in bilayer capacitance(C_dl), and a higher apparent exchange current density than the pure Pb and Pb-Ag-Ca composite anodes. The oxygen evolution potential steady-state potential was 1.528 V at a current density of 500 A·m^-2, which was 125 mV lower than that of the pure Pb electrode. Furthermore, the corrosion rate was reduced by 31.6%, which provided excellent oxygen evolution catalytic activity and corrosion resistance.更多还原