AVENA marcelo Javier
Clay–magnetite co-aggregates for efficient magnetic removal of organic and inorganic pollutants
PECINI, ELIANA; AVENA, MARCELO
Año: 2021 vol. 11
This work reports the behavior of montmorillonitemagnetite mixtures of varying composition in aqueous dispersions and evaluates their adsorbing properties using a cationic organic pollutant, methylene blue (MB+ ), and an anionic inorganic pollutant, arsenate (As(V)), as the adsorb-ing species. The effects of the presence of montmorillonite on the As(V) adsorption by magnetite and the effects of magnetite on the MB+ adsorption by the clay were specially addressed. The simple mix-ture of a montmorillonite dispersion with a magnetite dispersion led to the spontaneous formation of montmorillonitemagnetite co-aggregates. These co-aggregates showed a unimodal electrophoretic mobility distribution, with no evidence of the presence of separate populations of montmorillonite or magnetite. The application of a magnetic field confirmed the formation of co-aggregates and showed that their separation rate increased as the magnetite content increased. Adsorption studies as a function of the aggregate composition demonstrated that MB+ uptake was mainly controlled by the content of montmorillonite, while As(V) adsorption was mainly controlled by the content of Fe3 O4 . This permits an easy tuning of the adsorbing properties of cations and anions by controlling the composition of the system.