Removal of an emergent contaminant by a palygorskite from Pontezuela/Cuban region

Abstract

Water pollution associated to pharmaceutical and personal care products has become a serious environmental issue. A reasonable strategy to mitigate the problem involves adsorbing materials. In particular, the use of clays is an advantageous alternative considering their high adsorption capacity and compatibility with the environment. In the present work, the efficacy of an unmodified Cuban clay (palygorskite, Pal) as nanosupport of sulfamethoxazole (SMX)—an antibiotic considered an emerging contaminant (EC) was demonstrated. In order to establish the best conditions to increase the drug capture by the clay, the influence of physical–chemical parameters was studied. The amount of SMX incorporated onto the clay was determined by UV spectroscopy. The resulting composite material was characterized by infrared spectroscopy (IR), X-ray diffraction (XRD), thermogravimetric analysis (TG/DTG), zeta potential (ZP), nitrogen adsorption measurements, transmission electron microscopy (TEM) and scanning electron microscopy with energy dispersive spectroscopy (SEM–EDS). Drug desorption studies were performed on the SMX-charged clay, indicating the reversibility of the incorporation process. The results suggest the potential use of Cuban natural palygorskite for water decontamination.