生物炭作为修复重金属污染的热门材料,虽然在吸附方面具有一定的优势,但其有限的比表面积和孔体积已无法满足更高的吸附需求。通过优化生物炭的孔隙结构,可以显著提高其表面性能,从而增加吸附量。综述了原材料选择、热解温度、加热速率和时间对生物炭孔隙结构形成的影响,重点探讨了物理活化(如气体活化)和化学活化(包括酸碱和金属改性)对孔隙扩展的机理与存在的不足之处。最后,介绍了孔隙扩展生物炭在重金属吸附中的应用,旨在为开发具有丰富孔结构和高吸附性能的生物炭提供理论依据和实践指导。
Biochar (BC) is widely regarded as a prominent material for the remediation of heavy metal contamination,offering certain advantages in adsorption processes.However,the limited specific surface area and pore volume of biochar frequently prove inadequate for meeting increasingly stringent adsorption requirements.Optimization of the biochar pore structure presents a viable strategy for significantly enhancing its surface properties,thereby increasing adsorption capacity.The influence of feedstock selection,pyrolysis temperature,heating rate,and residence time on the development of the biochar pore structure was examined.Significant attention was directed towards the mechanisms and inherent limitations of pore expansion techniques,encompassing physical activation (e.g.,gas activation) and chemical activation involving treatments with acids,alkalis,or metal-containing compounds.Finally,the application of pore-expanded biochar in heavy metal adsorption was presented,aiming to furnish theoretical underpinnings and practical guidelines for the future development of biochar with enriched pore structures and superior adsorption performance.
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基金资助
国家自然科学基金(41473122;41173113)
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