Application of Anodic Oxidation with Graphite Electrodes in Pretreated Leachates

• 作者: C. M. García-Lara H. A. Nájera-Aguilar J. A. Araiza-Aguilar J. A. Bautista-Ramírez J. H. Casta?ón-González R. F. Gutiérrez-Hernández T. J. Sánchez-Sánchez
• 来源期刊: 应用科学(英文)
• 学科: 地球科学
• 关键词: Anodic OXIDATION GRAPHITE ELECTRODES ADVANCED OXIDATION PROCESSES
• 年，卷（期）: 2020,（3）
• 页码范围: 69-77
• 页数: 9页
• 分类号: X70

摘要

Currently, landfills are the main method used for the final disposal of urban solid waste. The degradation processes that waste goes through in these sites, alongside rainwater that percolates through them, generate highly polluting liquids (leachate). In the treatment of leachate, advanced oxidation processes (AOP) can significantly reduce the concentrations of different pollutants. Due to the high documented potential around AOPs, in this study, the effectiveness of anodic oxidation in the removal of the remaining organic load in leachates pretreated in a biological system was evaluated. Graphite electrodes were used as anode and cathode. The efficiency of anodic oxidation, in terms of the removal of chemical oxygen demand (COD) and color, was evaluated under different current densities (7, 12, 17 and 22 mA/cm2) and pH values (3, 4.5 and 6). Under the best conditions found (22 mA/cm2 and pH of 6) and with an oxidation time of 5 hours, a maximum removal of 68% in COD and 91% in color was achieved, which represented a quality in the final effluent of 271 mg/L and 151 Pt-Co in COD and color, respectively. Therefore, considering that graphite is an economic and widely available material, the results obtained show anodic oxidation, with the use of graphite electrodes, as a technically viable alternative as a final purification stage for pretreated leachates.