Absorbed radiation and kinetic model in photocatalysis by TiO2

The current work studies a novel and affordable methodology to estimate and quantify the photon flux absorbed and the amount of light that leaves from an illuminated photocatalytic system with TiO2 suspended in water. To achieve it, a new parameter BFSwat-λ is defined and presented. It indicates, fo...

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Detalles Bibliográficos
Autores: Bayarri Ferrer, Bernardí, Giménez Farreras, Jaume, Curcó, David, Esplugas Vidal, Santiago
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/184669
Acceso en línea:https://hdl.handle.net/2445/184669
Access Level:acceso abierto
Palabra clave:Diòxid de titani
Fotocatàlisi
Radiació
Titanium dioxide
Photocatalysis
Radiation
Descripción
Sumario:The current work studies a novel and affordable methodology to estimate and quantify the photon flux absorbed and the amount of light that leaves from an illuminated photocatalytic system with TiO2 suspended in water. To achieve it, a new parameter BFSwat-λ is defined and presented. It indicates, for every wavelength, the fraction of the incoming radiation which is not absorbed by the system. BFSwat-λ was estimated by means of actinometric experiments in a jacketed reactor and a model based on Beer-Lambert law. For wavelengths below 388 nm and TiO2 concentrations between 0.05 and 2 g L−1, experimental values of BFSwat-λ were between 0.77 and 0.27. In the second part of the work, a simple kinetic model, which breaks down the effect of incident radiation and kinetic constant, is developed. For this, the photon flux absorbed by TiO2, previously determined, was included in the model. This new model was tested in the photocatalytic degradation of 2,4-dichlorophenol under different TiO2 concentrations. The kinetic model fits satisfactorily the experimental values and a new kinetic constant kʹ ap [mol·L−1 Einstein−1] was obtained, which is independent of the amount of catalyst loaded to the system. This achievement may be very useful for an easy initial comparison, design or scaling up of different photocatalytic reactors with similar geometry.