Iron/zinc and phosphoric acid modified sludge biochar as an efficient adsorbent for fluoroquinolones antibiotics removal

Yongfei Ma; Ping Li; Lie Yang; Li Wu; Liuyang He; Feng Gao; Xuebin Qi; Zulin Zhang

doi:10.1016/j.ecoenv.2020.110550

Iron/zinc and phosphoric acid modified sludge biochar as an efficient adsorbent for fluoroquinolones antibiotics removal

Ecotoxicol Environ Saf. 2020 Jun 15:196:110550. doi: 10.1016/j.ecoenv.2020.110550. Epub 2020 Apr 1.

Authors

Yongfei Ma¹, Ping Li², Lie Yang³, Li Wu⁴, Liuyang He¹, Feng Gao², Xuebin Qi², Zulin Zhang⁵

Affiliations

¹ Hubei Key Laboratory of Mineral Resources Processing and Environment, School of Resources and Environmental Engineering, State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan, 430070, China.
² China-UK Water and Soil Resources Sustainable Utilization Joint Research Centre, Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences, Xinxiang, 453002, China.
³ Hubei Key Laboratory of Mineral Resources Processing and Environment, School of Resources and Environmental Engineering, State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan, 430070, China. Electronic address: yanglie612@whut.edu.cn.
⁴ Hubei Key Laboratory of Mineral Resources Processing and Environment, School of Resources and Environmental Engineering, State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan, 430070, China. Electronic address: wuli774@whut.edu.cn.
⁵ Hubei Key Laboratory of Mineral Resources Processing and Environment, School of Resources and Environmental Engineering, State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan, 430070, China; The James Hutton Institute, Craigiebuckler, Aberdeen, AB15 8QH, UK. Electronic address: Zulin.Zhang@hutton.ac.uk.

PMID: 32247244
DOI: 10.1016/j.ecoenv.2020.110550

Abstract

Iron/zinc (Fe/Zn), phosphoric acid (H₃PO₄) or in combination (Fe/Zn + H₃PO₄) modified sludge biochar (SBC) were prepared and tested in this study to adsorb fluoroquinolones antibiotics including ciprofloxacin (CIP), norfloxacin (NOR) and ofloxacin (OFL) from water. Fe/Zn + H₃PO₄-SBC had an increased surface area (S_BET), total pore volume (V_tot), mesoporous volume (V_mes), pore diameter (D_p) and oxygen-containing functional groups. It exhibited superior adsorption performance for CIP, NOR and OFL with the maximum adsorption amount of 83.7, 39.3, 25.4 mg g^-1, respectively. Pseudo-second kinetic and Freundlich isotherm model presented the better fitting. The results of models and characterization analysis in combination indicated that physisorption and chemisorption, including pore filling, hydrogen bonding, π-π interaction, electrostatic interaction and functional groups complexation on a heterogeneous surface were the dominant process and mechanism. Liquid film diffusion was the main rate-limiting step. The adsorption process of CIP, NOR and OFL onto Fe/Zn + H₃PO₄-SBC were a spontaneous endothermic process. This study demonstrated that Fe/Zn + H₃PO₄ modified SBC exhibited high adsorption capacity, which was a promising adsorbent for fluoroquinolones as well as for other antibiotics effective removal from waters.

Keywords: Adsorption mechanism; Fluoroquinolones antibiotics; Iron/zinc; Phosphoric acid; Sludge biochar; Water.

MeSH terms

Adsorption
Anti-Bacterial Agents / analysis*
Charcoal / chemistry*
Fluoroquinolones / analysis*
Iron / chemistry
Kinetics
Models, Theoretical
Phosphoric Acids / chemistry
Sewage / chemistry*
Surface Properties
Water Pollutants, Chemical / analysis*
Water Purification / methods*
Zinc / chemistry

Substances

Anti-Bacterial Agents
Fluoroquinolones
Phosphoric Acids
Sewage
Water Pollutants, Chemical
biochar
Charcoal
Iron
phosphoric acid
Zinc