Graphene oxide (GO) is hydrophilic and possess large surface area. It is an adsorbent to remove contaminants from aqueous solutions, with the potential of enhancing the degradation of compounds during oxidation. Pharmaceuticals have been detected in the environment repeatedly and are known to be difficultly removed in conventional treatment technologies. Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID) for treatment of pain and inflammatory diseases. Chlorphenamine is used to prevent allergic conditions and is one of the typical medicine in small-animal veterinary practice. In this study, GO-iron oxide (GO-Fe3O4) composite was synthesized by co-precipitation for effective expulsion from water due to the nano-size dimension of GO after treatment through a magnetic field. This presentation investigates the adsorption and catalytic degradation of diclofenac and chlorphenamine in batch experiments by applying GO-Fe3O4 composite as the adsorbent and/or catalyst, with hydrogen peroxide or ozone being added as the oxidant. In the results, although the performances varied between two pharmaceuticals, the adsorption onto the surface of the GO-Fe3O4 composite and catalytic degradation of diclofenac and chlorphenamine were observed. The removals of diclofenac and chlorphenamine via adsorption and catalytic reaction were separately quantified. The treatment efficiencies of two pharmaceuticals varied, particular in the presence of H2O2, potentially attributable to their different mechanisms for removals. However, the treatment efficiencies of two compounds were both affected by adjusting the iron content in the GO-Fe3O4 composite, and reaction pH. The variations of the specific surface area and inter-planar spacing of the GO-Fe3O4 composite given different ratios of iron to GO during preparation, changing its performances for adsorption and degradation of the pharmaceuticals tested in this study.

Synergy of graphene oxide-iron oxide composite and hydrogen peroxide for adsorption and degradation of diclofenac and chlorphenamine in water

2019 Fall National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.