Degradation of persistent pharmaceuticals in aqueous solutions by a positive dielectric barrier discharge treatment

The degradation of the pharmaceuticals carbamazepine, clofibric acid, and iopromide in aqueous and landfill leachate containing solutions by corona discharge over a liquid surface was investigated. Two barrier electrodes, which provided an atmospheric pressure corona, were mounted above a transport roll, which moved a thin water film of test solution from the sample reservoir. Numerous tests were performed on single, mixed, and landfill leachate containing solutions with various combinations of powers, rotational speeds, air gaps, and exhaust restrictions. Best results were obtained with the highest rotational speed, a reduced exhaust, and an electrode air gap of 1.5 mm.