Degradation of paracetamol in aqueous solution: Comparison of different UV induced advanced oxidation processes

Abstract

Environmental hazards are a consequence of the massive use of synthetic chemicals that are prevalent in nearly every aspect of modern life. The outburst of the socalled "emerging pollutants" (pharmaceuticals and pesticides among others) generates an additional problem due to the scarce available information on their impact on the environment or their interferences with the biological processes. Among them, paracetamol is one of the drugs the most widely found in hospital effluents, in the effluents of wastewater treatment plants, as well as in rivers. In this work, the feasibility of paracetamol degradation by different processes based on ultraviolet radiation is discussed: photolysis, photooxidation with hydrogen peroxide, photo-Fenton reaction, and heterogeneous photocatalysis with TiO2 are evaluated. The best results are obtained with the photo-Fenton process, for which more than 99% of the pharmaceutical is degraded within 5 minutes. At best experimental conditions the mineralization was superior to 75% after one hour of reaction.