Photocatalytic degradation of pharmaceuticals using graphene based materials

Abstract

Pharmaceutical products are produced purposely for the treatment of diseases with the aim of improving human health. Despite their usefulness to human and animal health, pharmaceuticals are now being regarded as emerging environmental pollutants. This is due to their increased use and the fact that they are indiscriminately discharged into the aquatic environment from hospitals, households, industries, pharmacies, as well as leakages and leachates from municipal wastewater treatment plants and landfill sites. Moreover, the conventional methods of wastewater treatment were not designed with these emerging pollutants in mind resulting in the discharge of untreated or incomplete treated wastewater into water bodies. Pharmaceuticals in water are believed to exert deleterious effects on humans and aquatic organisms. The concern to remove these pharmaceutical wastes and their metabolites from wastewater before their final discharge into water bodies has culminated in the development of a wide variety of other treatment technologies such as adsorption, chemical oxidation, liquid extraction, biodegradation, and so on. However, because these pharmaceuticals are mostly water soluble and non-biodegradable, most of the treatment techniques are inappropriate for their effective removal. The deployment of an appropriate technique for effective degradation of pharmaceutical wastes in water has therefore become a necessary requirement. This chapter therefore provides a detailed discussion on pharmaceuticals in general, their occurrence in water and their health consequences. It also delved into the photocatalytic degradation of these chemicals in water with emphasis on the use of graphene based materials.