The University of Queensland, Advanced Water Management Centre (AWMC), Brisbane, QLD 4072, Australia.
Water Res. 2011 Nov 1;45(17):5381-8. doi: 10.1016/j.watres.2011.07.033. Epub 2011 Aug 6.
Hydrogen sulfide generation is a major issue in sewer management. A novel method based on electrochemical sulfide oxidation was recently shown to be highly effective for sulfide removal from synthetic and real sewage. Here, we compare the performance of five different mixed metal oxide (MMO) coated titanium electrode materials for the electrochemical removal of sulfide from domestic wastewater. All electrode materials performed similarly in terms of sulfide removal, removing 78±5%, 77±1%, 85±4%, 84±1%, and 83±2% at a current density of 10 mA/cm(2) using Ta/Ir, Ru/Ir, Pt/Ir, SnO(2) and PbO(2), respectively. Elevated chloride concentrations, often observed in coastal areas, did not entail any significant difference in performance. Independent of the electrode material used, sulfide oxidation by in situ generated oxygen was the predominant reaction mechanism. Passivation of the electrode surface by deposition of elemental sulfur did not occur. However, scaling was observed in the cathode compartment. This study shows that all the MMO coated titanium electrode materials studied are suitable anodic materials for sulfide removal from wastewater. Ta/Ir and Pt/Ir coated titanium electrodes seem the most suitable electrodes since they possess the lowest overpotential for oxygen evolution, are stable at low chloride concentration and are already used in full scale applications.
硫化氢的生成是污水管理中的一个主要问题。最近，一种基于电化学硫化物氧化的新方法被证明在从合成和实际污水中去除硫化物方面非常有效。在这里，我们比较了五种不同的混合金属氧化物（MMO）涂覆钛电极材料在电化学去除生活污水中硫化物的性能。所有电极材料在去除硫化物方面表现相似，在电流密度为 10 mA/cm(2) 时，Ta/Ir、Ru/Ir、Pt/Ir、SnO(2) 和 PbO(2) 分别去除了 78±5%、77±1%、85±4%、84±1%和 83±2%。在沿海地区经常观察到的高氯浓度并没有导致性能有任何显著差异。无论使用哪种电极材料，原位生成的氧气的硫化物氧化都是主要的反应机制。通过元素硫的沉积使电极表面钝化的情况并没有发生。然而，在阴极室中观察到结垢现象。本研究表明，研究中所有的 MMO 涂覆钛电极材料都是从废水中去除硫化物的合适阳极材料。Ta/Ir 和 Pt/Ir 涂覆钛电极似乎是最合适的电极，因为它们具有最低的氧气析出过电位，在低氯浓度下稳定，并且已经在全规模应用中使用。
