title: Combination of carboxymethyl chitosan-coated magnetic nanoparticles and chitosan-citrate complex gel beads as a novel magnetic adsorbent.
abstract: Magnetic chitosan beads were synthesized by incorporating N,O-carboxymethyl chitosan-coated magnetic nanoparticles (NOCC-MNPs) into chitosan-citrate gel beads (CCGBs) for adsorbing Cu(II) ions. An increase of Cu(II) adsorption capacity was due to the combined chelation effects from the electron-donating functional groups in the CCGBs and NOCC-MNPs. Moreover, the paramagnetic susceptibility of Cu(II) citrate chelates could further improve the Cu(II) adsorption efficiency through the force of magnetic attraction. The adsorption data of the magnetic CCGBs fitted well with the Freundlich model, whereas the adsorption kinetics followed the pseudo-second-order kinetic model. The maximal adsorption capacity as estimated by the Langmuir model was 294.11mg/g. The adsorption thermodynamic parameters indicated that the involved process should be spontaneous and exothermic.
authors.affiliation: Department of Biochemistry and Molecular Cell Biology, School of Medicine, Taipei Medical University, Taipei 110, Taiwan; Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei 110, Taiwan.
authors.forename: Fwu-Long
authors.initials: FL
authors.lastname: Mi
authors.affiliation: Department of Chemical Engineering, Ming Chi University of Technology, New Taipei City 243, Taiwan. Electronic address: sjwu@mail.mcut.edu.tw.
authors.forename: Shao-Jung
authors.initials: SJ
authors.lastname: Wu
authors.affiliation: Department of Chemical Engineering, Ming Chi University of Technology, New Taipei City 243, Taiwan.
authors.forename: Yung-Chih
authors.initials: YC
authors.lastname: Chen
mesh_terms: D000327:Adsorption; D048271:Chitosan / Q000737:chemistry*; D005782:Gels / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D058185:Magnetite Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D008863:Microspheres; D017550:Spectroscopy, Fourier Transform Infrared; D013816:Thermodynamics; D014961:X-Ray Diffraction
chemical_list: D005782:Gels; D058185:Magnetite Nanoparticles; C408130:chitosan citrate; C077199:O,N-carboxymethylchitosan; D048271:Chitosan
keywords: Adsorption; Chitosan; Citrate; Magnetic nanoparticles