Kinetics and removal pathwayof basic fuchsin by electrochemical oxidization

Abstract

Abstract In present paper Basic Fuchsin was decomposed by electrochemical oxidization (EO).Kinetic parameters, dominant reaction routes, intermediates, energy cost evaluation and biotoxicity were also discussed systematically.Decolorization of Basic Fuchsin by potentiostatic experiments was fitted to be pseudo first-order reaction. The apparent rate constants were obtained as 7.33 × 10−4, 1.46 × 10−3, 1.71 × 10−3, 2.29 × 10−3 and 3.9 × 10−3 min−1 at temperatures of 293, 303, 313, 323 and 333 K, respectively. The apparent activation energy was calculated as 30.82 kJ·mol−1 at 1.2 Vvs.SCE. The diffusion coefficient D, electron transfer number and the transfer coefficientβwere 1.66 × 10−7 cm2/s, 1 and 0.775, respectively. The current-time integral curve manifested that the total electric quantity consumed was only 3.37C compared with theoretical full oxidation electrical charge quantity 140C in anode cell. Sediments of Basic Fuchsin largely decreased the electrical energy consumption. According to Xevo-G2-Qtof-MS, the main reaction process included electropolymerization reaction,oxidation cleavage reaction, free radical reaction and open ring reaction. OH and Cl were the main free radicals. They attacked Basic Fuchsin to form di-polymer or tri-polymer precipitates. Furthermore, the acute toxicity assessment showed that this degradation process could greatly reduce the eco-toxicity of Basic Fuchsin.