Zhang Jining, Lü Fan, Zhang Hua, Shao Liming, Chen Dezhen, He Pinjing
1] State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China [2] Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, China.
State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China.
Sci Rep. 2015 Mar 24;5:9406. doi: 10.1038/srep09406.
Sewage sludge biochars were obtained at different pyrolysis temperatures from 300°C to 900°C and their macro- and microscale properties were analyzed. The biochar's plant-available nutrients and humus-like substances in the water-extractable phase and fixed nutrients in the solid fraction were evaluated for their potential agronomic implications. FT-IR, Raman, XRD, XPS, and SEM techniques were used to investigate the chemical structure, functional groups, and microcrystal structure on the surface of the biochar. The results revealed minor chemical changes and dramatic mass loss in the biochar obtained at 300-500°C, whereas significant chemical changes in the biochar were obtained at 600-900°C. The concentrations of plant-available nutrients as well as fulvic- and humic-acid-like materials decreased in the biochar samples obtained at higher temperatures. These results implied that the biochar samples pyrolyzed at 300-500°C could be a direct nutrient source and used to neutralize alkaline soil. The surface area and porosity of the biochar samples increased with temperature, which increased their adsorption capacity. Rearrangement occurred at higher temperature 600-900°C, resulting in the biochar becoming increasingly polyaromatic and its graphite-like carbon becoming organized.
在300°C至900°C的不同热解温度下制备了污水污泥生物炭，并对其宏观和微观性质进行了分析。评估了生物炭在水提取相中植物可利用的养分和类腐殖质物质以及固体部分中的固定养分，以探讨其潜在的农学意义。利用傅里叶变换红外光谱（FT-IR）、拉曼光谱、X射线衍射（XRD）、X射线光电子能谱（XPS）和扫描电子显微镜（SEM）技术研究了生物炭表面的化学结构、官能团和微晶结构。结果表明，在300-500°C下获得的生物炭有轻微的化学变化和显著的质量损失，而在600-900°C下获得的生物炭有显著的化学变化。在较高温度下获得的生物炭样品中，植物可利用养分以及类富里酸和类腐殖酸物质的浓度降低。这些结果表明，在300-500°C下热解的生物炭样品可以作为直接的养分来源，并用于中和碱性土壤。生物炭样品的表面积和孔隙率随温度升高而增加，这提高了它们的吸附能力。在600-900°C的较高温度下发生了重排，导致生物炭的多芳构化程度增加，其类石墨碳变得更加有序。
