Degradation of norfloxacin by calcite activating peroxymonosulfate: Performance and mechanism

Ziyang Chu; Tianhu Chen; Haibo Liu; Dong Chen; Xuehua Zou; Hanlin Wang; Fuwei Sun; Peixun Zhai; Min Xia; Meng Liu

doi:10.1016/j.chemosphere.2021.131091

Degradation of norfloxacin by calcite activating peroxymonosulfate: Performance and mechanism

Chemosphere. 2021 Nov:282:131091. doi: 10.1016/j.chemosphere.2021.131091. Epub 2021 Jun 5.

Authors

Ziyang Chu¹, Tianhu Chen¹, Haibo Liu², Dong Chen¹, Xuehua Zou¹, Hanlin Wang¹, Fuwei Sun¹, Peixun Zhai¹, Min Xia¹, Meng Liu¹

Affiliations

¹ Key Laboratory of Nano-minerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei, 230009, China; Institute of Environmental Minerals and Materials, School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, 230009, China.
² Key Laboratory of Nano-minerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei, 230009, China; Institute of Environmental Minerals and Materials, School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, 230009, China. Electronic address: liuhaibosky116@hfut.edu.cn.

PMID: 34119731
DOI: 10.1016/j.chemosphere.2021.131091

Abstract

In this study, calcite was investigated as an activator for the norfloxacin (NOR) degradation by peroxymonosulfate (PMS). Under optimum conditions, the NOR removal percentage was 99.7% within 60 min, and the pseudo-first-order kinetics effectively described the two-stage oxidation process. The NOR removal percentage improved from 10.4% to 91.5% and the reaction rate constant elevated from 0.0010 to 0.1217 min^-1 when 0.5 g/L calcite was added compared to that without calcite addition. Furthermore, the results of radical scavenger and electron spin resonance trapping indicated that the favorable alkaline environment and a proper level of carbonate in the Calcite/PMS system facilitated the activation of PMS to generate ¹O₂ for rapid NOR degradation. Compared with NaOH, calcite was able to maintain the pH (8-9) of the reaction system stable. Besides, the content of anions with buffering capacity and organic matter in the water matrix influenced the removal percentage of NOR. Seven intermediates were identified and the NOR degradation pathways were suggested. The findings of this research provided an environmentally friendly activator for remediation of organic wastewater and deepened the understanding of the interaction between calcium carbonate and PMS.

Keywords: Activation; Calcite; Norfloxacin; Peroxymonosulfate; Singlet oxygen.

MeSH terms

Calcium Carbonate*
Norfloxacin*
Peroxides
Wastewater

Substances

Peroxides
Waste Water
peroxymonosulfate
Calcium Carbonate
Norfloxacin