Removal of antipyrine through two-dimensional and three-dimensional electrolysis: comparison, modification, and improvement

Abstract

In this work, removal of antipyrine was studied through two-dimensional (2D) and three-dimensional (3D) electrolysis. 2D electrolysis was firstly studied with the Ti/SnO2-Ta2O5-IrO2 anode as working electrode. Operating parameters affecting antipyrine removal, such as current density, electrode distance, and initial concentration of antipyrine, were investigated and optimized. As the limited antipyrine removal efficiency of 48.0% was not satisfying, 3D electrolysis with γ-Al2O3 as particle electrodes was introduced in the purpose of improving the antipyrine removal. An obviously enhanced removal efficiency of 78.3% was obtained, which seemingly validated the effect of particle electrodes in improving antipyrine removal. Hence, an effort to further enhance the antipyrine removal efficiency was made through improving the electrochemical characteristics of γ-Al2O3 as particle electrodes. Modified Sn-Sb-Bi/γ-Al2O3 particles were thus prepared through impregnation method. And a desirable antipyrine removal efficiency of 94.4% and energy consumption of 0.18 kWh/g antipyrine were achieved in the 3D electrolysis with Sn-Sb-Bi/γ-Al2O3 as particle electrodes. Furthermore, possible mechanism and pathway of antipyrine degradation in 3D electrolysis were explored through detection of ·OH using terephthalic acid fluorescent probe method and detection of antipyrine degradation intermediates using LC-MS.