Centro de Tecnologia
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Article Effects of different structure-directing agents (SDA) in MCM-41 on the adsorption of CO2(Journal of Porous Materials, 2014) Melo, Marcus Antonio de Freitas; Costa, C. C.; Melo, Dulce Maria de Araújo; Mendoza, M. E.; Nascimento, J. C.; Andrade, J. M.; Barros, J. M. F.Article Pyrolysis kinetics of elephant grass pretreated biomasses(Springer, 2014) Melo, Marcus Antonio de Freitas; Braga, Renata Martins; Costa, Tiago Roberto da; Freitas, Julio C. O.; Barros, Joana Maria de Farias; Melo, Dulce Maria de AraújoArticle Síntese e caracterização de materiais mesoporosos modificados com níquel para a captura de CO2(Cerâmica - Associação Brasileira de Cerâmica, 2014) Melo, Marcus Antonio de Freitas; Nascimento, Alexsandra Rodrigues do; Figueredo, Gilvan Pereira de; Rodrigues, G.; Souza, Marcelo José Barros de; Melo, Dulce Maria de AraújoArticle Kinetic study of CTMA+ removal from the pores of the Ti-MCM-41 molecular sieve(Journal of Thermal Analysis and Calorimetry, 2014) Melo, Marcus Antonio de Freitas; Fontes, Maria do Socorro Braga; Melo, Dulce Maria de Araújo; Barros, Joana Maria de Farias; Braga, Renata Martins; Fontes, Vilsinéia dos AnjosArticle Caracterização físico-mecânica e ambiental de cerâmica estrutural com imobilização do íon manganês(Cerâmica Industrial, 2013) Melo, Marcus Antonio de Freitas; Câmara, Ana Paula Costa; Medeiros, Leonardo Coutinho de; Macedo, Daniel Araújo de; Galdino, José Nildo; Melo, Dulce Maria de AraújoArticle Kinetic study of template removal of MCM-41 derived from rice husk ash(Journal of Thermal Analysis and Calorimetry, 2013) Melo, Marcus Antonio de Freitas; Braga, Renata Martins Braga; Barros, Joana Maria de Farias Barros; Melo, Dulce Maria de Araújo; Aquino, Flávia de Medeiros; Freitas, Júlio Cézar de Oliveira; Santiago, Rodrigo CésarArticle Síntese e caracterização de espinélios à base de ferritas com gelatina como agente direcionador(Cerâmica, 2012) Melo, Marcus Antonio de Freitas; Costa, Asenete Frutuoso; Pimentel, Patrícia Mendonça; Melo, Dulce Maria de Araújo; Aquino, Flávia de MedeirosThe ferrites with spinel type structure comprise a group of magnetic materials very well established. However, improvements and innovations are still happening seeking new applications and optimization of preparation techniques. Among the materials with spinel structure, the ferrite stand out because they have a broad technological importance in the area of materials, with applications in humidity and oxygen sensors, microwave materials, pigments, magnetic materials and electrical, catalytic hydrogenation, thin fi lms ceramic tiles, among others. In this work spinel-type CuFe2 O4 and CuFeCr2 O4 were synthesized using gelatin as directing agent with the purpose of producing nanosized homogeneous particles through a simple, fast and affordable method. The ferrites were characterized by thermal analysis, X-ray diffraction, infrared spectroscopy and scanning electron microscopy. The results confi rmed the feasibility of the used synthesis routeArticle Gelatin synthesis of CuFe2O4 and CuFeCrO4 ceramic pigments(Materials Letters, 2013) Melo, Marcus Antonio de Freitas; Costa, Asenete Frutuoso; Pimentel, Patrícia Mendonça; Aquino, Flávia de Medeiros; Melo, Dulce Maria de Araújo; Santos, Ieda Maria Garcia dosArticle Adsorção de Cu2+ e Cr3+ em efluentes líquidos utilizando a cinza do bagaço da cana-de-açúcar(Associação Brasileira de Cerâmica - ABCeram, 2015) Melo, Marcus Antônio de Freitas; Ferreira, P. P. L.; Braga, Renata Martins; Teodoro, N. M. A.; Melo, Vítor Rodrigo de Melo e; Melo, Dulce Maria de AraújoThe liquid effluents of some industries have traces of harmful metals having bioaccumulative property, which contributes to the increase in their toxicity. Given the industrial growth, and the consequent increase in contaminant emissions in wastewater, the adsorption is among the operations applied to decrease the concentrations of metals in order to meet current environmental regulations. The residual biomass has been gaining attention in the treatment of these effluents by a renewable material and cost as compared with conventional adsorbents. The present work aims to evaluate the ashes of the efficiency of sugarcane bagasse (CBC) on the adsorption of metal ions Cu2+ and Cr3+, through isotherm adsorption tests. The CBC was characterized regarding its microstructure, chemical composition, specific surface area and morphology, and the adsorbate was analyzed by flame atomic absorption. The CBC has performed effectively as a bioadsorbent for both synthetic solutions containing Cu2+ and Cr3+ ions present in liquid effluents. The isotherms adsorption showed a growing profile, indicating the average removal efficiency of 97.3% to 96.4% Cr3+, and Cu2+ to, this material can be applied as an adsorbent in industrial effluentsArticle Effect of the acid treatment of montmorillonite clay in the oleic acid esterification reaction(ABM, ABC, ABPol, 2015) Melo, Marcus Antônio de Freitas; Nascimento, Alexsandra Rodrigues do; Alves, José Antônio Barros Leal Reis; Melo, Dulce Maria de Araújo; Souza, Marcelo José Barros de; Pedrosa, Anne Michelle Garrido