Activated peracetic acid by Mn3O4 for sulfamethoxazole degradation: A novel heterogeneous advanced oxidation process. (November 2022)

• Record Type: Journal Article
• Authors: Zhou, Runyu; Zhou, Gaofeng; Liu, Yiqing; Liu, Shenglan; Wang, Shixiang; Fu, Yongsheng
• Is Part Of: Chemosphere. Volume 306(2022)
• Publication Date: 2022-11
• Subjects: Peracetic acid -- Heterogeneous catalysis -- Mn3O4 -- Organic radicals -- Sulfamethoxazole; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2022.135506
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: In this study, a novel peracetic acid (PAA)-based advanced oxidation process using Mn3 O4 as a catalyst was proposed. A thorough sulfamethoxazole (SMX) removal could be achieved within 12 min in Mn3 O4 /PAA system at neutral pH. The characterization results of fresh and used Mn3 O4 suggested that ≡Mn(II), ≡Mn(III) and ≡Mn(IV) on Mn3 O4 were the Mn species for PAA activation, constituting the redox cycles of ≡Mn(II)/≡Mn(III) and ≡Mn(III)/≡Mn(IV) simultaneously. Organic radicals (i.e., CH3 C(O)O and CH3 C(O)OO ) were verified to be the dominant reactive species responsible for SMX degradation in Mn3 O4 /PAA system by radical scavenging experiments. The neutral condition was the most favorable pH for SMX removal in Mn3 O4 /PAA system and the increase of PAA or Mn3 O4 dosage could enhance SMX degradation. Presence of HCO3 − and natural organic matter (NOM) could inhibit SMX degradation, while Cl −, NO3 − and SO4 2− had a negligible effect on SMX removal. The thorough SMX removal in successive experiments and characterization results of used Mn3 O4 suggested the good reusability and stability of Mn3 O4 for PAA activation. Based on six detected transformation products of SMX, hydroxylation, nitration, bond cleavage and coupling reaction were proposed to be its degradation pathways in Mn3 O4 /PAA system. Graphical abstract: Image 1 Highlights: Mn3 O4 was firstly applied to activate PAA to degrade SMX. ≡Mn(II), ≡Mn(III) and ≡Mn(IV) in Mn3 O4 were the main active sites for PAA activation. CH3 C(O)O. and CH3 C(O)OO were the dominant reactive species for SMX degradation. Mn3 O4 showed a good stability and reusability for PAA activation to degrade SMX. Four possible degradation pathways of SMX in Mn3 O4 /PAA system were proposed.