School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, People's Republic of China.
Environ Sci Pollut Res Int. 2020 Aug;27(22):28132-28145. doi: 10.1007/s11356-020-09166-5. Epub 2020 May 15.
To evaluate the adsorption mechanism and performance of phosphate onto the composite of low-cost biochar and iron oxide, four biochar-iron oxides, namely biochar-magnetite (BC-M), biochar-ferrihydrite (BC-F), biochar-goethite (BC-G), and biochar-hematite (BC-H), were prepared by fabricating iron oxide to porous biochar. The biochar-iron oxides had huge surface areas of 691-864 m/g and average pore diameters of 3.4-4.0 nm. Based on the characterization analysis of FTIR, XRD, XPS, and zeta potential, the interactions of electrostatic attraction, ligand exchange, and deposition dominated the phosphate adsorption onto biochar-iron oxides. The maximum adsorption capacity of phosphate followed the order of BC-G > BC-F > BC-H > BC-M. The isotherm data of BC-M and BC-H were well fitted by the Langmuir and Freundlich models, while those of BC-G and BC-F followed the Langmuir model. In addition, BC-M, BC-F, BC-G, and BC-H owned excellent regeneration ability and adsorption performance in practical (simulated) wastewater environment. Then the biochar-iron oxides exerted extensive and satisfactory prospect in wastewater remediation and recycling application in soil.
为了评估低价生物炭和氧化铁复合材料对磷酸盐的吸附机制和性能，通过将氧化铁制备到多孔生物炭上，制备了四种生物炭-氧化铁，即生物炭-磁铁矿（BC-M）、生物炭-水铁矿（BC-F）、生物炭-针铁矿（BC-G）和生物炭-赤铁矿（BC-H）。生物炭-氧化铁具有 691-864 m/g 的巨大比表面积和 3.4-4.0nm 的平均孔径。基于 FTIR、XRD、XPS 和动电位的表征分析，静电吸引、配体交换和沉积的相互作用主导了磷酸盐在生物炭-氧化铁上的吸附。磷酸盐的最大吸附容量依次为 BC-G>BC-F>BC-H>BC-M。BC-M 和 BC-H 的等温线数据很好地符合 Langmuir 和 Freundlich 模型，而 BC-G 和 BC-F 的等温线数据则符合 Langmuir 模型。此外，BC-M、BC-F、BC-G 和 BC-H 在实际（模拟）废水环境中具有优异的再生能力和吸附性能。然后，生物炭-氧化铁在废水修复和土壤中回收应用方面具有广泛而令人满意的前景。
