Promotion removal of aniline with electro-Fenton processes utilizing carbon nanotube 3D morphology modification of an Ag-loaded copper foam cathode

Abstract Aniline is a refractory pollutant with high toxicity that will cause pollution if discharged without treatment. However, conventional technology cannot meet the requirements of safe disposal. It is necessary to develop novel treatment technology to address this problem, and the electro-Fenton process could be a solution. In this study, a novel CNT-Ag@Cu cathode was synthesized by Ag doping and multiwall carbon nanotube (CNT) 3D morphology modification of copper foam (CF). The composition, structure and morphology of CNT-Ag@Cu were obtained. The aniline removal rate was over 99% under optimal conditions. The kinetic analysis results indicated that aniline removal followed a pseudo-first-order kinetic law, and the reaction rate constant reached 0.0661 min−1. The aniline removal rate also reached 99.2% after the CNT-Ag@Cu cathode was used 10 times without further treatment. The CNT-Ag@Cu cathode had an excellent ability to maintain an OH concentration that reached 0.5 μmol/L after 60 min of reaction. Aniline removal is a coupling multimechanism in which Ag loading improves H2O2 generation and the nanoconfinement effect of CNTs promotes accumulation of a high concentration of OH.