Optimization of hydrocalumite preparation under microwave irradiation for recovering aluminium from a saline slag

Aluminium was successfully extracted by treating an aluminium slag with aqueous NaOH under reflux conditions. This solution was purified by precipitation of silicon species by addition of HCl up to pH = 1, and used for preparing hydrocalumite (Ca2Al(OH)6Cl·2H2O) by the coprecipitation method. The ef...

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Detalles Bibliográficos
Autores: Jiménez, Alejandro, Misol, Alexander, Morato, Álvaro, Rives, Vicente, Vicente, Miguel Ángel, Gil Bravo, Antonio
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
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:2454/41500
Acceso en línea:https://hdl.handle.net/2454/41500
Access Level:acceso abierto
Palabra clave:Aluminium recovery
Crystallinity
Hydrocalumite
Layered double hydroxide
Microwaves ageing
Saline slag
Descripción
Sumario:Aluminium was successfully extracted by treating an aluminium slag with aqueous NaOH under reflux conditions. This solution was purified by precipitation of silicon species by addition of HCl up to pH = 1, and used for preparing hydrocalumite (Ca2Al(OH)6Cl·2H2O) by the coprecipitation method. The effect of temperature on the properties of hydrocalumite prepared under microwave (MW) irradiation was studied. Characterization of the obtained solid was carried out by powder X-ray diffraction (PXRD), thermal analysis, FT–IR spectroscopy, chemical analysis, electron microscopy and N2 adsorption–desorption at −196 °C. The results showed that the use of the extracted aluminium solution allowed to obtain hydrocalumite by the coprecipitation method and that the temperature of the MW ageing treatment had a large effect on the formation of side phases, in addition to hydrocalumite. The results here reported demonstrate that formation of hydrocalumite is an effective method for the recovering of aluminium from its waste.