Pure niobia as catalyst for the oxidation of organic contaminants: Mechanism study via ESI-MS and theoretical calculations

被引:63
作者
Oliveira, Luiz C. A.
Ramalho, Teodorico C.
Goncalves, Maraisa
Cereda, Flavia
Carvalho, Kele T.
Nazzarro, Marcelo S.
Sapag, Karim
机构
[1] Univ Fed Lavras, Dept Quim, BR-37200000 Lavras, MG, Brazil
[2] UNSL, Dept Fis, Lab Ciencias Superficies & Med Porosos, RA-5700 San Luis, Argentina
关键词
D O I
10.1016/j.cplett.2007.08.037
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
In this work, synthetic and natural niobium oxide (niobia), were used to promote the oxidation of methylene blue dye. The samples were characterized by XRD, XPS and FTIR measurements. The presence of reactive species on the surface of the samples strongly increases the oxidation rate of the methylene blue dye. The reaction mechanism was studied by ESI-MS analyses. Moreover, kinetic data and XPS spectroscopy suggest that the oxidation of the organic dye involves oxidizing species mainly generated after previous treatment with H2O2. The results also showed that the oxidation takes place by a homolytic mechanism via radical intermediates. (C) 2007 Elsevier B.V. All rights reserved.
引用
收藏
页码:133 / 137
页数:5
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