Novos materiais baseados em nióbia e óxidos de ferro para degradação catalítica de corantes em meio aquoso

L. C. A. OLIVEIRA, M.GONÇALVES, M.C. GUERREIRO, J. D. FABRIS, P.R. C. COUCEIRO, K. SAPAG

Foz do Iguazu

Congreso; 13 º Cong Bras. de Cat. 3º Cong. Cat do Mercosul; 2005

SBCaT

In this work, composites based on niobia (Nb2O5) and iron oxides were tested as catalysts on the oxidation of the textiledye red reactive, in a hydrogen peroxide medium. The composites were prepared as a mixture of niobia:iron oxides at ratiosof 1:1 (sample labeled nióbia 1/1), 1:5 (nióbia 1/5) and 5:1 (nióbia 5/1). Pure samples of niobia and iron oxide were alsoused. The composites were characterized with the programmed reduction temperature technique, 57 Fe Mössbauer and FT-infraredspectroscopies and powder X-ray diffractometry. Results show that the samples are formed by a mixture of niobiaand iron oxides, namely goethite (ideal formula, aFeOOH) and maghemite (gFe2O3) The composite nióbia 1/1 showed thehighest activity, completely decolorizing the dye substrate in 1 h reaction.