Effect of key operational parameters on the photocatalytic oxidation of phenol by nanocrystalline sol-gel TiO2 under UV irradiation

• Tipo: Artigo em Revista Científica Internacional
• Data: 2009

Autores

Claudia Gomes Silva (Autor) FEUP; Joaquim Luis Faria (Autor) FEUP

Revista

Título: Journal of Molecular Catalysis A: Chemical

Vol. 305

Páginas: 147-154

ISSN: 1381-1169

Editora: Elsevier B.V.

Indexação

ISI Proceedings

ISI Web of Knowledge - 77 Citações

ISI Web of Science

Scopus - 85 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Química

CORDIS: Ciências Tecnológicas

Outras Informações

ID Authenticus: P-003-J7J

DOI: 10.1016/j.molcata.2008.12.015

Abstract (EN): Nanocrystalline TiO2 materials Produced by an acid-catalyzed sol-gel method are used as catalysts ill the photocatalytic degradation of phenol under ultraviolet light. Materials with different crystalline and morphological properties are obtained by controlling the temperature used in the calcination step. Induced light conversion and adsorption have opposite dependencies oil the light intensity. The operational parameters (nature of TiO2 crystal phase, catalyst concentration, pH and initial phenol concentration) have the expected influence in the efficiency of the photocatalytic degradation process. The effect of two different co-oxidants (H2O2 and Na2S2O8) in the photocatalytic process is also described. A modified Langmuir-Hinshelwood kinetic model is used considering a pseudo-steady state approach in order to explain the dependence of both, the kinetic rate and adsorption equlibrium constants, on light intensity. Hydroquinone and catechol are the main intermediates of the photocatalytic reaction, as result from the reaction of phenol with photogenerated hydroxyl radicals. A possible degradation pathway is advanced.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 8