Synergistic catalysis induced by a multicomponent system constructed with combined DBD plasma, g-C3N4/FOD and persulfate for trichloroethylene removal

A multicomponent system consisting of dielectric barrier discharge (DBD), g-C 3 N 4 /FOD composite catalysis, and persulfate (PS) oxidation was successfully constructed for synergistically degrading trichloroethylene. The successful preparation of the g-C 3 N 4 /FOD composite catalyst material was confirmed through various testing methods, including Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectrometer (FT-IR), X-ray Photoelectron Spectroscopy (XPS) and Electrochemical workstation. Under this composite system, trichloroethylene degradation efficiency in water reached 93.2 % after an 8-minute reaction. Thermal gravimetric analysis (TG) and cyclic usage experiments both demonstrated the excellent stability of the g-C 3 N 4 /FOD catalyst removal efficiency of the composite as concentration, DBD discharge voltage and carrier gas flow rate, g-C 3 N 4 /FOD dose, and PS concentration. Optimal treatment conditions were determined through response surface methodology (RSM) experiments. Within a reaction time of 30 min, a total organic carbon (TOC) removal rate of 87.4 % was achieved, effectively reducing intermediate product formation and making the combined process more environmentally friendly than individual treatments. Experimental evidence SO 4 − , OH and O 2− played dominant roles during trichloroethylene degradation in water. Gas chromatography–mass spectrometry analysis identified potential pathways for trichloroethylene degradation and revealed two major intermediate products. Toxicity prediction results for these degradation products showed lower acute toxicity and chronic toxicity compared to the precursor compound.