Agro‐Industrial Wastes Composites as Novel Adsorbents

Abstract

Defective green coffee (DGC), coffee silverskin (CS) and spent coffee grounds (SCG), three major byproducts of the coffee industry, were magnetically modified by treatment with an aqueous ferrofluid containing magnetite nanoparticles and characterized by SEM, XRD and FTIR. In order to assess their suitability as adsorbents for the removal of pollutants from wastewaters, adsorption and regeneration studies were carried out using methylene blue as a model contaminant. All the materials exhibited high adsorption capacity and the adsorption rate varied in the order: CS > SCG > DGC. In addition, their adsorption capacity remained almost unchanged for at least six adsorption/desorption cycles. These results strongly support their use as new low-cost adsorbents for environmental applications.