Adsorption of reactive dyes on titania-silica mesoporous materials

This paper presents a study on the adsorption of two basic dyes, methylene blue (MB) and rhodamine B (RhB), from aqueous solution onto mesoporous silica-titania materials. The effect of dye structure, adsorbent particle size, TiO2 presence, and temperature on adsorption was investigated. Adsorption...

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Detalles Bibliográficos
Autores: Messina, Paula Verónica, Schulz, Pablo Carlos
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2006
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/95339
Acceso en línea:http://hdl.handle.net/11336/95339
Access Level:acceso abierto
Palabra clave:ADSORPTION
DECONTAMINATION
ENERGETIC SURFACE HETEROGENEITY
ISOTHERMS
KINETICS
REACTIVE DYES
SILICA-TITANIA MESOPOROUS MATERIALS
SURFACTANT TEMPLATES
THERMODYNAMIC
TIO2 NANOPARTICLES
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
Descripción
Sumario:This paper presents a study on the adsorption of two basic dyes, methylene blue (MB) and rhodamine B (RhB), from aqueous solution onto mesoporous silica-titania materials. The effect of dye structure, adsorbent particle size, TiO2 presence, and temperature on adsorption was investigated. Adsorption data obtained at different solution temperatures (25, 35, and 45 °C) revealed an irreversible adsorption that decreased with the increment of T. The presence of TiO2 augmented the adsorption capacity ( qe ). This would be due to possible degradation of the dye molecule in contact with the TiO2 particles in the adsorbent interior. The adsorption enthalpy was relatively high, indicating that interaction between the sorbent and the adsorbate molecules was not only physical but chemical. Both Langmuir and Freundlich isotherm equations were applied to the experimental data. The obtained parameters and correlation coefficients showed that the adsorption of the two reactive dyes (MB and RhB) on the adsorbent systems at the three work temperatures was best predicted by the Langmuir isotherm, but not in all cases. The kinetic adsorption data were processed by the application of two simplified kinetic models, first and second order, to investigate the adsorption mechanism. It was found that the adsorption kinetics of methylene blue and rhodamine B onto the mesoporous silica-titania materials surface under different operating conditions was best described by the first-order model.