화학공학소재연구정보센터
Chemical Engineering Journal, Vol.330, 345-354, 2017
Enhanced degradation performance of sulfisoxazole using peroxymonosulfate activated by copper-cobalt oxides in aqueous solution: Kinetic study and products identification
In recent years, numerous studies have been concentrated on enhancing the efficiency of SO4 center dot- based advanced oxidation processes (AOPs) on eliminating contaminants. In this study, an efficacious heterogeneous copper-cobalt catalyst (Cu0.39Co1.01O4.57) was synthesized by a simple coprecipitation method to activate peroxymonosulfate (PMS) to degrade sulfisoxazole (SIX). On the surface of this catalyst, active sites like Co2+, Co3+ and Cu2+ were found. In the optimal condition, SIX could be completely degraded in 30 min at ambient temperature, pH=7 and by 1.87 mM PMS and 0.1 g L-1 Cu0.39Co1.01O4.57. The addition of this catalyst also enhanced the degradation of other 5 sulfonamides (SAs). The possible catalytic mechanism was discussed that Co2+ first formed Co(OH)(+), then it activated PMS to produce sulfate radicals, and Cu2+ on the surface may participate in reducing Co3+. Twelve transformation products of SIX by PMS were identified by HPLC-MS/MS analysis. The degradation mechanism of SIX in PMS/Cu0.39Co1.01O4.57 system was proposed, which is comprised of four pathways. Both experiments and theoretical calculations demonstrate that N7, C2 and C6 on the aniline ring, and the -S-N- and -O-N- bonds are the most active sites to be attacked by oxidizing species.