Study of tetracycline removal and saturated resin regenerated by dielectric barrier discharge plasma

The wastewater produced by the large-scale usage of antibiotics worldwide was more harmful to the ecological environment and human health. In the research, the coupling technology of ‘adsorption-plasma regeneration’ was taken to treat tetracycline in aqueous solution. The pollutants were adsorbed by the resins firstly and then regenerated ectopically by dielectric barrier discharge plasma. The discharge parameters, such as discharge voltage and frequency were researched to achieve the optimal regeneration efficiency and energy efficiency. Meanwhile, the analyses of the surface functional groups and microstructure were also investigated. After the five ‘adsorption-regeneration’ processes, the results showed that the optimal discharge parameters of voltage and frequency were 20 kV and 1 kHz, respectively. The regeneration efficiency and energy efficiency were above 80% and 115 g kW⁻¹ ·h⁻¹, respectively. The tetracycline adsorption by virgin resin and regenerated resin nearly followed pseudo-second order kinetics, and there was no fatal damage to the surface characteristics and physicochemical properties of the resins through the multiple plasma regeneration processes. Finally, according to the intra-particle diffusion model and the degradation products detected by GC-MS, the adsorption and degradation mechanisms of tetracycline were deduced.