Efficient microwave-assisted mineralization of oxytetracycline driven by persulfate and hypochlorite over Cu-biochar catalyst

Qiaozhi Zhang; Yuqing Sun; Weijian Xu; Yang Cao; Chunfei Wu; Chi-Hwa Wang; Daniel C W Tsang

doi:10.1016/j.biortech.2023.128698

Efficient microwave-assisted mineralization of oxytetracycline driven by persulfate and hypochlorite over Cu-biochar catalyst

Bioresour Technol. 2023 Mar:372:128698. doi: 10.1016/j.biortech.2023.128698. Epub 2023 Jan 31.

Authors

Qiaozhi Zhang¹, Yuqing Sun², Weijian Xu³, Yang Cao³, Chunfei Wu⁴, Chi-Hwa Wang⁵, Daniel C W Tsang⁶

Affiliations

¹ Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China; Research Centre for Resources Engineering towards Carbon Neutrality, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
² School of Agriculture, Sun Yat-sen University, Guangzhou, Guangdong 510275, China.
³ Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
⁴ School of Chemistry and Chemical Engineering, Queen's University Belfast, 39 Stranmillis Road, David Keir Building, BT9 5AG Belfast, United Kingdom.
⁵ Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, 117576, Singapore.
⁶ Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China; Research Centre for Resources Engineering towards Carbon Neutrality, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China. Electronic address: dan.tsang@polyu.edu.hk.

PMID: 36731614
DOI: 10.1016/j.biortech.2023.128698

Abstract

Microwave (MW)-assisted catalytic degradation of organic pollutants draws increasing attention owing to its high efficiency in wastewater treatment. This work developed Cu-loaded biochar (CuBC) catalysts for time-efficient mineralization of refractory and high-concentration oxytetracycline (OTC). With only 1 min at 80 °C, Na₂S₂O₈ achieved 100% total organic carbon (TOC) removal over the Cu5BC, while NaClO mineralized 73.3% TOC over the metal-free BC, in contrast to a relatively low mineralization efficiency (< 35%) achieved by H₂O₂. The high efficiency in MW-assisted oxidation systems could be ascribed to reactive oxidizing species (^•SO₄^- or ^•ClO), which otherwise were barely detectable in a conventional heating system. The interactions between CuBC and MW were revealed by correlating the physiochemical characteristics to the MW absorption ability. The proposed catalytic systems can contribute to the development of a high-throughput and low-carbon wastewater treatment technology.

Keywords: Advanced oxidation; Engineered biochar; Industrial wastewater treatment; Microwave activation; Pharmaceuticals and personal care products.

MeSH terms

Carbon
Hydrogen Peroxide
Hypochlorous Acid
Microwaves
Oxidation-Reduction
Oxytetracycline*
Wastewater
Water Pollutants, Chemical* / analysis

Substances

biochar
Wastewater
Hypochlorous Acid
Hydrogen Peroxide
Oxytetracycline
Carbon
Water Pollutants, Chemical