title: Synthesis and adsorption characteristics of an heterogenized manganese nanoadsorbent towards methyl orange.
abstract: Heterogeneous Mn nanoparticles (5-30 nm diameter) is found to be a nanomaterial for the rapid removal of large quantities of toxic dye (methyl orange) from aqueous solution, with wide ranging potential applications. The synthesized materials were characterized with different methods such as FT-IR spectroscopy, CHN elemental analysis, BET, SEM, TEM, ICP-OES and EPR. The contact time to obtain equilibrium for maximum adsorption of methyl orange was 20 min. EPR of Mn ions evidenced that most of the covalently bond active sites of the nano-adsorbent are in the form of Mn(III) ions at the surface. The heterogeneous Mn(III)-Cl ions were found to be effective adsorbent for the removal of methyl orange from solution. The adsorption of methyl orange ions has been studied in terms of pseudo-first-order and pseudo-second-order kinetics, and the Freundlich, Langmuir and Langmuir-Freundlich isotherm models have also been applied to the equilibrium adsorption data. The adsorption process was spontaneous and endothermic in nature and followed pseudo-second-order kinetic model.
authors.affiliation: Department of Chemistry, Shiraz Branch, Islamic Azad University, P.O. Box 71955-149, Shiraz, Fars, Iran. Electronic address: m-arshadi@ch.iut.ac.ir.
authors.forename: M
authors.initials: M
authors.lastname: Arshadi
authors.affiliation: Department of Chemistry, Faculty of Science, University of Zabol, Zabol, Iran.
authors.forename: M
authors.initials: M
authors.lastname: Mehravar
authors.affiliation: Department of Water Engineering, College of Agriculture, Fasa University, 74617-81189 Fasa, Iran.
authors.forename: M J
authors.initials: MJ
authors.lastname: Amiri
authors.affiliation: Young Researchers and Elite Club, Pharmaceutical Sciences Branch, Islamic Azad University, Tehran, Iran.
authors.forename: A R
authors.initials: AR
authors.lastname: Faraji
mesh_terms: D000327:Adsorption; D001391:Azo Compounds / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D008345:Manganese / Q000737:chemistry*; D008854:Microscopy, Electron / Q000379:methods; D036103:Nanotechnology; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D001391:Azo Compounds; D008345:Manganese; C100258:methyl orange
keywords: Adsorption; Immobilization; Methyl orange; Mn nanoparticle