title: Hierarchical MWCNTs/Fe₃O₄/PANI magnetic composite as adsorbent for methyl orange removal.
abstract: Multi-wall carbon nanotubes (MWCNTs) decorated with Fe3O4 nanoparticles (MWCNTs/Fe3O4) were modified by polyaniline (PANI). The adsorption kinetics of methyl orange (MO) on MWCNTs/Fe3O4/PANI could be fitted well by the pseudo-second-order model. The adsorption of MO on MWCNTs/Fe3O4/PANI was strongly dependent on pH values. The Langmuir isotherm model fitted MO adsorption isotherm better than the Freundlich model. The hierarchical MWCNTs/Fe3O4/PANI showed high adsorption capacity toward ionic dyes (446.25 mg g(-1) for MO and 417.38 mg g(-1) for Congo red (CR)). The nitrogen-containing functional groups of PANI decorated on MWCNTs/Fe3O4/PANI contributed to many effective adsorption sites and thus increased the adsorption capacity toward MO and CR. Moreover, PANI prevented Fe3O4 nanoparticles from dissolution, and hence improved the stability of MWCNTs/Fe3O4/PANI in solution. The experimental results showed that the MWCNTs/Fe3O4/PANI composite was a promising magnetic material for the preconcentration and separation of ionic dye pollutants from aqueous solutions in environmental pollution cleanup.
authors.affiliation: College of Resources and Environmental Sciences, Henan Agricultural University, Zhengzhou 450002, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: College of Tobacco Science, Henan Agricultural University, Zhengzhou 450002, PR China. Electronic address: chenhonglili06@163.com.
authors.forename: Hongli
authors.initials: H
authors.lastname: Chen
authors.affiliation: Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei 230031, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.affiliation: Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei 230031, PR China. Electronic address: clchen@ipp.ac.cn.
authors.forename: Changlun
authors.initials: C
authors.lastname: Chen
keywords: Adsorption; Carbon nanotubes; Methyl orange; Polyaniline