title: Chitosan/maghemite composite: a magsorbent for the adsorption of methyl orange.
abstract: In this study, magnetic beads were prepared by encapsulation of magnetic nanoparticles in epichlorohydrin cross-linked chitosan beads. Their adsorption characteristics were assessed by using methyl orange (MO) as an adsorbate. MO adsorption onto chitosan beads was found to be optimal in the pH range of 3-5. The adsorption isotherm was well described by the Langmuir model and showed high MO adsorption capacity (2.38 mmol/g, i.e. 779 mg/g). MO adsorption kinetics followed a pseudo-second-order kinetic model, indicating that adsorption was the rate-limiting step. At 0.305 mmol/L, only 19 min was required to reach 90% adsorption and 50% of the MO was adsorbed in 2 min. Desorption studies of MO using NaOH showed the reusability of the magsorbent. No release of iron species was observed at pH>2.4.
authors.affiliation: UPMC Univ. Paris 06, Physicochimie des Electrolytes Colloïdes et Sciences Analytiques (PECSA) (CNRS UMR 7195), 75252 Paris, France; Eau et Industrie 14, Rue des Écoles St-Nicolas-des-Eaux, 56930 Pluméliau, France. Electronic address: layaly.obeid@upmc.fr.
authors.forename: Layaly
authors.initials: L
authors.lastname: Obeid
authors.forename: Agnès
authors.initials: A
authors.lastname: Bée
authors.forename: Delphine
authors.initials: D
authors.lastname: Talbot
authors.forename: Soukeina
authors.initials: S
authors.lastname: Ben Jaafar
authors.forename: Vincent
authors.initials: V
authors.lastname: Dupuis
authors.forename: Sébastien
authors.initials: S
authors.lastname: Abramson
authors.forename: Valérie
authors.initials: V
authors.lastname: Cabuil
authors.forename: Mathias
authors.initials: M
authors.lastname: Welschbillig
keywords: Adsorption; Chitosan; Dye; Ferrofluid; Magnetic; Magsorbent; Methyl orange; γ-Fe(2)O(3)