Effects of ph and water matrix on photoinduced degradation of antibiotic cefdinir

Abstract

In this paper, photolytic and photocatalytic degradation of cephalosporin antibiotic cefdinir dissolved in MilliQ water and in synthetic municipal wastewater are described. Both degradation processes were based on UV-A and UV-C radiation. The UV-A-based oxidation processes have been less efficient in terms of irradiation time required for complete degradation of cefdinir than the UV-C-based processes. The effect of pH value was observed for photocatalytic processes in terms of slower degradation under basic conditions than acidic and neutral conditions. It was also confirmed that different wastewater components could significantly reduce the degradation rate of cefdinir in UV-A-based processes. Although UV-A radiation experiments need more time than UV-C experiments for complete degradation of cefdinir, they have a potential for practical use since such reactor configuration could use natural solar radiation as a source of UV-A radiation and therewith significantly reduce the costs of pharmaceuticals degradation treatment step.