title: A friendly environmental material: iron oxide dispersed over activated carbon from coffee husk for organic pollutants removal.
abstract: A friendly environmental material for organic contaminants removal was prepared in this work: small particles of iron oxide dispersed over activated carbon from coffee waste for Fenton-like application. The materials were characterized by means of XRD, N2 physisorption, Mössbauer spectroscopy and H2 pulse titration. The composites showed very good catalytic performances for methylene blue organic dye oxidation. The small goethite particles are the predominant iron oxide phase in the composites. The apparent surface area is quite high and is not very affected after iron impregnation. ESI-MS studies revealed that the dye removal occurs through a Fenton-type system by the composite whereas for the activated carbon the dye removal occurs mainly via adsorption. The iron leaching from the catalysts was negligible, less than 0.5 ppm, which evidences the occurrence of a heterogenous oxidation process. The catalyst was very active for methylene blue oxidation and could be repeatedly used for at least 5 cycles. The catalyst was also active in the oxidation of other organic compounds, such as caffeine and atrazine.
authors.affiliation: Departamento de Química, Universidade Federal de Lavras, Caixa Postal 37, CEP 37200-000 Lavras, MG, Brazil. maraisa_g@yahoo.com.br
authors.forename: Maraísa
authors.initials: M
authors.lastname: Gonçalves
authors.forename: Mário César
authors.initials: MC
authors.lastname: Guerreiro
authors.forename: Luiz Carlos Alves
authors.initials: LC
authors.lastname: de Oliveira
authors.forename: Cinthia Soares
authors.initials: CS
authors.lastname: de Castro
mesh_terms: D000327:Adsorption; D002110:Caffeine / Q000737:chemistry; D002606:Charcoal / Q000737:chemistry*; D040503:Coffea; D004785:Environmental Pollutants / Q000737:chemistry*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D005290:Ferric Compounds / Q000737:chemistry*; D008751:Methylene Blue / Q000737:chemistry; D010084:Oxidation-Reduction; D010636:Phenols / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D015204:Spectroscopy, Mossbauer
chemical_list: D004785:Environmental Pollutants; D005290:Ferric Compounds; D010636:Phenols; D002606:Charcoal; C000499:ferric oxide; D002110:Caffeine; D008751:Methylene Blue
keywords: Activated carbon; Environmental application; Goethite; Oxidation; Pollutants