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 文獻名： Magnetic Fe3O4 Nanoparticles Modified With Polyethyleneimine for the Removal of Pb(II)

作者： Hongmei Jiang,Menglan Sun,Jiangyan Xu,Aimin Lu,Ying Shi

摘要：Preparation of polyethyleneimine functionalized magnetic Fe3O4 by using a one-step solvothermal method is reported in this paper. The effect of the amount of polyethyleneimine on the properties of the prepared materials including the shape, size, and adsorption performance was investigated in detail. The magnetic adsorbent with the best adsorption capacity was prepared and used for the removal of Pb(II) in an aqueous medium. Adsorption experiments were performed to evaluate the effect of different sorption parameters, such as pH, initial concentration of Pb2+, and contact time. Langmuir and pseudo-second-order models were used for isotherm and kinetic studies, through which a maximum adsorption capacity of 143 mg g−1 could be calculated. Pb(II) could be desorbed from magnetic Fe3O4 nanoparticles modified with polyethyleneimine by 0.5 mol L−1 HCl and used for five cycles without any adsorption performance loss, indicating that the polymeric magnetic adsorbent used in this work had good reusability and great potential for practical application.