title: Magnetized manganese oxide nanocomposite for effective decontamination of Cd(II) from wastewaters.
abstract: In this study, a composite with magnetic properties has been successfully synthesized by a novel and environmentally friendly route and is applied to Cd(II) adsorption for water decontamination. The quantification of the phases obtained by Rietveld refinement has shown the presence of 84% of Mn3O4and 16% of Fe3O4. Transmission electron microscopy image shows an aggregate of Mn3O4nanoparticles without specific orientation and the predominance of octahedral morphology with nanoparticles size estimated around 25-30 nm. The Cd(II) adsorption isotherm is fitted using the Langmuir-Freundlich model. The estimated maximum adsorption capacities of Cd(II) at pH 6 and 7 are similar (0.28 ± 0.02 and 0.31 ± 0.02 mg/m2, respectively). The kinetic results show that the studied system follows the pseudo-second-order model. The Raman results indicate that Cd is being specifically adsorbed by the Mn3O4in the composite. The hysteresis curve of the composite Mn3O4/Fe3O4has changed when compared to the pure magnetite; however, the coercive field after the addition of manganese oxide remains unaltered and does not change with a value around 158 Oe. The turbidity tests showed that the magnetic sedimentation was efficient and promising for wastewater treatment in large scale. These materials can be conveniently recovered by magnetic separation, avoiding the filtration steps, which will make easier the solid-liquid separation operation that follows the adsorption process.
authors.affiliation: Department of Materials Engineering, Centro Federal de Educação Tecnológica de Minas Gerais (CEFET-MG), Av. Amazonas, 5253, Nova Suíça, Belo Horizonte, Minas Gerais 30421-169, Brazil.
authors.forename: Ana Pacheli
authors.initials: AP
authors.lastname: Heitmann
authors.affiliation: National Institute of Science and Technology on Mineral Resources, Water and Biodiversity (INCT-Acqua), Brazil.
authors.forename: Gabriela C
authors.initials: GC
authors.lastname: Silva
authors.affiliation: Department of Materials Engineering, Centro Federal de Educação Tecnológica de Minas Gerais (CEFET-MG), Av. Amazonas, 5253, Nova Suíça, Belo Horizonte, Minas Gerais 30421-169, Brazil; National Institute of Science and Technology on Mineral Resources, Water and Biodiversity (INCT-Acqua), Brazil.
authors.forename: Paulo Renato P
authors.initials: PR
authors.lastname: Paiva
authors.affiliation: Department of Metallurgical and Materials Engineering, Universidade Federal de Minas Gerais (UFMG), Av. Antonio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais 31270901, Brazil; National Institute of Science and Technology on Mineral Resources, Water and Biodiversity (INCT-Acqua), Brazil.
authors.forename: Maria Sylvia S
authors.initials: MS
authors.lastname: Dantas
authors.affiliation: Department of Metallurgical and Materials Engineering, Universidade Federal de Minas Gerais (UFMG), Av. Antonio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais 31270901, Brazil; National Institute of Science and Technology on Mineral Resources, Water and Biodiversity (INCT-Acqua), Brazil.
authors.forename: Virginia S T
authors.initials: VS
authors.lastname: Ciminelli
authors.affiliation: Fundação Centro de Analise, Pesquisa e Inovação Tecnológica - FUCAPI - Gov. Danilo de Mattos Areosa, 381 - Distrito Industrial, Manaus, Amazonas CEP 69075-351, Brazil.
authors.forename: Isabel Cristina
authors.initials: IC
authors.lastname: Souza Dinóla
authors.affiliation: Department of Chemistry, Centro Federal de Educação Tecnológica de Minas Gerais (CEFET-MG), Av. Amazonas, 5253, Nova Suíça, Belo Horizonte, Minas Gerais 30421-169, Brazil E-mail: angelamello@des.cefetmg.br; National Institute of Science and Technology on Mineral Resources, Water and Biodiversity (INCT-Acqua), Brazil.
authors.forename: Angela M
authors.initials: AM
authors.lastname: Ferreira
mesh_terms: D000327:Adsorption; D002104:Cadmium / Q000302:isolation & purification*; D003666:Decontamination; D007700:Kinetics; D059346:Magnets; D017895:Manganese Compounds / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D053761:Nanocomposites / Q000737:chemistry*; D053758:Nanoparticles; D010087:Oxides / Q000737:chemistry*; D062065:Wastewater; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D002104:Cadmium; D017895:Manganese Compounds; D010087:Oxides; D062065:Wastewater; D014874:Water Pollutants, Chemical; C027424:manganese oxide