Degradation of sulfamonomethoxine in solution using pulsed plasma discharge – identification of by-products and toxicity of treated solution to green algae

Abstract

This study investigated the degradation of sulfamonomethoxine (SMM) by pulsed plasma discharge. SMM was successfully degraded following the first-order kinetics model. The percentage removal of SMM was estimated by the total input energy of plasma discharge, which was dependent on the initial SMM concentration. In addition, three types of by-products were observed at an early reaction time, which were then degraded. In contrast, the ecotoxicity of the treated solution by plasma discharge was assessed by an acute toxicity test using the green alga Raphidocelis subcapitata. The plasma discharge in water generated hydrogen peroxide with a concentration higher than the EC50 for R. subcapitata. It is therefore necessary to remove H2O2 or prevent the generation of H2O2 for the degradation of antibiotics in solutions using plasma discharge. HIGHLIGHTS Sulfamonomethoxine (SMM) was successfully degraded following a first-order kinetic model using pulsed plasma discharge.; The percentage removal of SMM was estimated by the total input energy.; Three types of degradation products were found at early reaction times, which were then also degraded.; Plasma discharge in water generated hydrogen peroxide at a concentration higher than the EC50 for R. subcapitata.;

Keywords

• acute toxic test
• lc-ms/ms
• raphidocelis subcapitata
• radical