Zn-Ti-Al layered double hydroxides synthesized from aluminum saline slag wastes as efficient drug adsorbents

This work reports the synthesis of Zinc-Titanium-Aluminum (ZnTiAl) layered double hydroxides (LDH) with various proportions of Al[sbnd]Ti and a Zn/(Al[sbnd]Ti) molar ratio of 3:1 by the co-precipitation method. Two series, made with commercial aluminum (Al) and aluminum extracted from saline slags (...

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Detalles Bibliográficos
Autores: Santamaría Arana, Leticia, López Aizpún, María, García Padial, Marcos, Vicente, Miguel Ángel, Korili, Sophia A., Gil Bravo, Antonio
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2020
País:España
Institución:Universidad Pública de Navarra
Repositorio:Academica-e. Repositorio Institucional de la Universidad Pública de Navarra
OAI Identifier:oai:academica-e.unavarra.es:2454/36991
Acceso en línea:https://hdl.handle.net/2454/36991
Access Level:acceso abierto
Palabra clave:Aluminum industrial wastes
Adsorption removal of diclofenac
Hydrotalcite from saline slags
Layered double hydroxides
Adsorption removal of salicylic acid
Descripción
Sumario:This work reports the synthesis of Zinc-Titanium-Aluminum (ZnTiAl) layered double hydroxides (LDH) with various proportions of Al[sbnd]Ti and a Zn/(Al[sbnd]Ti) molar ratio of 3:1 by the co-precipitation method. Two series, made with commercial aluminum (Al) and aluminum extracted from saline slags (Al*), have been considered. Structural characterization and comparison of the two series has been made using powder X-ray diffraction (PXRD), Nitrogen physisorption at 77 K, Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Thermogravimetry measurements. The adsorption capacity of diclofenac and salicylic acid, as examples of emergent pollutants, by the different LDH on batch and fixed-bed column experiments has been analyzed. The effect of various parameters, such as the pH, the initial concentration of pollutant, the mass of adsorbent and the contact time, on the sorption behavior were studied and compared. The contact time to attain equilibrium for maximum adsorption was found to be between 100 and 400 min. The kinetic and equilibrium results were correlated to several adsorption and isotherm equation models. The synthesized materials were more effective in removing diclofenac than salicylic acid, being Zn6Al*2 the hydrotalcite that showed the highest adsorption capacity. The results showed a new application of a material obtained from the valorization of an industrial waste such as aluminum saline slags.