Thermal effect on sulfamethoxazole degradation in a trivalent copper involved peroxymonosulfate system

Hengxin Liu; Haoxi Dai; Shuang Wu; Ning Li; Beibei Yan; Guanyi Chen

doi:10.1016/j.jcis.2023.02.102

Thermal effect on sulfamethoxazole degradation in a trivalent copper involved peroxymonosulfate system

J Colloid Interface Sci. 2023 Jun 15:640:121-131. doi: 10.1016/j.jcis.2023.02.102. Epub 2023 Feb 24.

Authors

Hengxin Liu¹, Haoxi Dai¹, Shuang Wu¹, Ning Li², Beibei Yan¹, Guanyi Chen¹

Affiliations

¹ School of Environmental Science and Engineering, Tianjin University/Tianjin Key Lab of Biomass/Wastes Utilization, Tianjin 300072, China.
² School of Environmental Science and Engineering, Tianjin University/Tianjin Key Lab of Biomass/Wastes Utilization, Tianjin 300072, China. Electronic address: liningec@tju.edu.cn.

PMID: 36842418
DOI: 10.1016/j.jcis.2023.02.102

Abstract

Persulfate (PS) activated by thermal or homogeneous metals can generate reactive oxygen species (ROS) and high-valence-state metals for contaminants degradation, showing great potential for applications. However, thermal effect in peroxymonosulfate (PMS) system with high-valence-state metal is still ambiguous. In this study, divalent copper (Cu(II)) catalysis was taken to explore thermal effect on PMS performance. Results showed that the Sulfamethoxazole (SMX) removal efficiency in the Cu(II)/PMS system at 60 min increased by only 5.9% with temperature increase from 30 °C to 60 °C. Moreover, SMX removal efficiency was excellent at neutral or basic pH, best with PMS concentration of 2.4 mM, and slightly affected by Cu(II) concentration. The singlet oxygen (¹O₂) was identified as main active species at low temperature while sulfate radicals (SO₄^-) was more effective at high temperature with Cu(II) co-activation. Also, trivalent copper (Cu(III)) was an important active species. The higher Cu(III) content, the better SMX removal efficiency, but the stronger intermediates toxicity. In combination with removal efficiency and intermediates toxicity at different temperatures, 30 °C was the optimal reaction temperature. Overall, this study provides new perspective on utilization of waste heat and high-valence-state metal for organic wastewater treatment in PMS systems.

Keywords: Active species; Peroxymonosulfate; Sulfamethoxazole; Thermal effect; Trivalent copper.