Degradation of tetracycline in aqueous solution by persulphate assisted gas-liquid dielectric barrier discharge

In order to promote the decomposition of pollutants, potassium peroxodisulphate (PDS) has been added to a gas-liquid dielectric barrier discharge (DBD) reactor with rod plate configuration for processing tetracycline (TC) wastewater. The effects of applied voltage, PDS dose, discharge gap, initial pH and TC concentration are discussed. The results show that the addition of PDS can significantly improve the removal efficiency of TC, the kinetic constant and the energy utilization of DBD. Compared with DBD treatment alone, the removal efficiency of TC (80 mg/L) can be increased by 45.5% after adding 0.6 g/L PDS. The TC removal efficiency increases with the increase of applied voltage and the decrease of TC concentration and discharge gap. The PDS dose has an optimal value. Weakly alkaline conditions are conducive to the removal of TC. Inorganic ions (Cl- and NO3-) have a significant effect on removing TC. The overall findings suggest an effective method to remove organic pollutants in wastewater.