Photocatalytic degradation of propranolol hydrochloride in aqueous medium employing bentonite-TiO2 nanocomposites

Abstract

Propranolol hydrochloride, a widely used medication, contaminates water bodies as it’s not fully metabolized by humans. Conventional water treatment methods are ineffective against it, necessitating more advanced approaches like heterogeneous photocatalysis. TiO₂, often used as a photocatalyst, is typically combined with other materials to form nanocomposites, enhancing its activity. This study evaluated TiO₂ synthesized via sol–gel method with organophilized bentonite for propranolol removal. Composites were prepared through solvothermal treatment, and an experimental design assessed the TiO₂/bentonite ratio, time, and temperature of the solvothermal treatment effects on photocatalytic activity. Increasing these parameters led to a nanocomposite capable of removing over 99 % of propranolol in water after 60 min of adsorption followed by 150 min of photocatalysis. The nanocomposite remained active after four treatment cycles. Characterization revealed TiO₂ (anatase) nanoparticles with a size range of 6–13 nm dispersed in bentonite’s fine tubular structures. This research underscores the potential of TiO₂-based nanocomposites in addressing pharmaceutical contamination in water bodies efficiently.