Enhanced heterogeneous photo-Fenton-like degradation of tetracycline over CuFeO2/biochar catalyst through accelerating electron transfer under visible light

Shuaishuai Xin; Bingrui Ma; Guocheng Liu; Xiaoming Ma; Chunlei Zhang; Xiaohan Ma; Mengchun Gao; Yanjun Xin

doi:10.1016/j.jenvman.2021.112093

Enhanced heterogeneous photo-Fenton-like degradation of tetracycline over CuFeO₂/biochar catalyst through accelerating electron transfer under visible light

J Environ Manage. 2021 May 1:285:112093. doi: 10.1016/j.jenvman.2021.112093. Epub 2021 Feb 16.

Authors

Shuaishuai Xin¹, Bingrui Ma², Guocheng Liu³, Xiaoming Ma², Chunlei Zhang², Xiaohan Ma³, Mengchun Gao⁴, Yanjun Xin⁵

Affiliations

¹ Key Lab of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao, 266100, China; Qingdao Engineering Research Center for Rural Environment, College of Resources and Environment, Qingdao Agricultural University, Qingdao, 266109, China.
² Key Lab of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao, 266100, China.
³ Qingdao Engineering Research Center for Rural Environment, College of Resources and Environment, Qingdao Agricultural University, Qingdao, 266109, China.
⁴ Key Lab of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao, 266100, China; College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China. Electronic address: mengchungao@outlook.com.
⁵ Qingdao Engineering Research Center for Rural Environment, College of Resources and Environment, Qingdao Agricultural University, Qingdao, 266109, China. Electronic address: xintom2000@126.com.

PMID: 33607559
DOI: 10.1016/j.jenvman.2021.112093

Abstract

The visible-light induced heterogeneous photo-Fenton-like (HPF-like) process is regarded as a promising technique for organic pollutants degradation due to its efficient utilization of solar energy and high H₂O₂ activation activity. This study prepared the CuFeO₂/biochar catalysts via hydrothermal technique at no extra reductant and systematically investigated their band structure and photoelectric properties. The dispersed distribution of CuFeO₂ particles in CuFeO₂/biochar composites narrowed bandgap of CuFeO₂ and promoted electron transport of CuFeO₂. Compared with CuFeO₂, the CuFeO₂/biochar containing 1.0 g biochar in the preparation (CuFeO₂/biochar-1.0) possessed higher carrier density and longer photoelectron lifetime, which is beneficial to higher catalytic performance. The apparent rate constant for tetracycline as target pollutant degradation by CuFeO₂/biochar-1.0 was 2.0 times higher than that by CuFeO₂. The acquired optimum conditions for tetracycline degradation were 220 mg L^-1 CuFeO₂/BC-1.0, 22 mM H₂O₂ and pH 6.4 using response surface methodology. The quenching experiments and ESR analysis revealed that OH was the predominant active species, and photoelectron and O₂^- were auxiliary species. The photoelectron could promote in-situ recycling of Cu²⁺ to Cu⁺ and Fe³⁺ to Fe²⁺, which significantly improved H₂O₂ activation by CuFeO₂. The possible pathway of tetracycline was proposed according to intermediates identified by HPLC/MS. The toxicity analysis demonstrated that the overall toxicity of the identified intermediates was reduced in HPF-like system.

Keywords: Biochar; CuFeO(2); Electron transfer; Heterogeneous photo-Fenton-like degradation; Tetracycline; Visible light.

MeSH terms

Catalysis
Charcoal
Electron Transport
Electrons*
Hydrogen Peroxide*
Light

Substances

biochar
Charcoal
Hydrogen Peroxide