论文部分内容阅读
The magnetic iron oxide (Fe3O4) nanoparticles stabilized on the biochar were synthesized by fast pyrolysis of Fe(Ⅱ)-loaded hydrophyte biomass under N2 conditions.The batch experiments showed that magnetic biochar presented a large removal capacity (54.35 mg/g) at pH 3.0 and 293 K.The reductive co-precipitation of U(Ⅵ) to U(Ⅳ) by magnetic biochar was demonstrated according to X-ray diffraction,X-ray photoelectron spectroscopy and X-ray absorption near edge structure analysis.According to extended X-ray absorption fine structure analysis,the occurrence of U-Fe and U-U shells indicated that high effective removal of uranium was primarily inner-sphere coordination and then reductive co-precipitation at low pH.These observations provided the further understanding of uranium removal by magnetic materials in environmental remediation.