School of Environmental Engineering, Nanjing Institute of Technology, Nanjing, Jiangsu, P.R. China.
Institute of Soil and Solid Waste Pollution Control, School of Environmental Engineering, Nanjing Institute of Technology, Nanjing, Jiangsu, P.R. China.
Waste Manag Res. 2022 Mar;40(3):331-338. doi: 10.1177/0734242X211009966. Epub 2021 Apr 8.
Sludge-based activated carbons (SACs) prepared from sewage sludge and corn straw, were modified by ferric nitrate, and the unmodified SAC and modified SAC were used as the adsorbing agent to treat the landfill leachate, the elimination capacity for chemical oxygen demand (COD) and organic matter in leachate were studied. Based on this, the physicochemical properties of SACs and the components changes in leachate were analyzed and characterized by X-ray photoelectron spectroscopy and three-dimensional fluorescence spectroscopy. The results showed that under optimal experimental conditions, the elimination capacities of SAC372 for COD, biological oxygen demand over 5 days, and NH-N in the leachate were 81.58%, 54.73%, and 69.08%, respectively; while the adsorption capacities of modified SAC for these three substances were 86.25%, 63.51%, and 79.15%, respectively. The ferric nitrate modification improved the ability of SAC to eliminate COD and organic matter from leachate slightly, and made the adsorption occurred easily. The adsorption process of unmodified SAC was dominated by multi-layer adsorption, while the adsorption process of modified SAC was dominated by monolayer adsorption. The mass fraction of Fe (2p) in modified SAC remarkably increased, from 0.70% to 26.01%, organic functional groups certain phase of Fe oxides with different valence states were generated in SAC, which provided a substrate for iron-carbon micro electrolysis. After adsorbed by unmodified SAC and modified SAC adsorption, the total fluorescence intensity of in the leachate increased by 17.01% and 116.84%, respectively. Both two SACs could decompose the humic acid-like substances into aromatic protein organic compounds, and modified SAC could further decompose the soluble microbial byproduct-like substances.
以污水污泥和玉米秸秆为原料制备的基于污泥的活性炭（SAC），用硝酸铁进行改性，将未改性的 SAC 和改性的 SAC 用作吸附剂来处理垃圾渗滤液，研究了它们对渗滤液中化学需氧量（COD）和有机物的去除能力。在此基础上，通过 X 射线光电子能谱和三维荧光光谱分析和表征了 SAC 的物理化学性质以及渗滤液中各成分的变化。结果表明，在最佳实验条件下，SAC372 对 COD、5 天生物需氧量和渗滤液中 NH-N 的去除率分别为 81.58%、54.73%和 69.08%；而改性 SAC 对这三种物质的吸附容量分别为 86.25%、63.51%和 79.15%。硝酸铁改性略微提高了 SAC 从渗滤液中去除 COD 和有机物的能力，使吸附更容易发生。未改性 SAC 的吸附过程主要是多层吸附，而改性 SAC 的吸附过程主要是单层吸附。改性 SAC 中 Fe（2p）的质量分数显著增加，从 0.70%增加到 26.01%，SAC 中生成了具有不同价态的铁氧化物的特定相的有机官能团，为铁碳微电解提供了基质。经过未改性 SAC 和改性 SAC 吸附后，渗滤液中的总荧光强度分别增加了 17.01%和 116.84%。两种 SAC 都可以将腐殖酸类物质分解为芳香蛋白类有机化合物，改性 SAC 还可以进一步将可溶性微生物产物类物质分解。
