Biochar-TiO2 magnetic nanocomposites for photocatalytic solar-driven removal of antibiotics from aquaculture effluents

Carla Patrícia Silva; Diogo Pereira; Vânia Calisto; Manuel A Martins; Marta Otero; Valdemar I Esteves; Diana L D Lima

doi:10.1016/j.jenvman.2021.112937

Biochar-TiO₂ magnetic nanocomposites for photocatalytic solar-driven removal of antibiotics from aquaculture effluents

J Environ Manage. 2021 Sep 15:294:112937. doi: 10.1016/j.jenvman.2021.112937. Epub 2021 Jun 10.

Authors

Carla Patrícia Silva¹, Diogo Pereira², Vânia Calisto³, Manuel A Martins⁴, Marta Otero⁵, Valdemar I Esteves³, Diana L D Lima³

Affiliations

¹ CESAM, Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal. Electronic address: patricia.silva@ua.pt.
² CESAM, Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal; CESAM, Department of Environment and Planning, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
³ CESAM, Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
⁴ CICECO, Department of Materials and Ceramic Engineering, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
⁵ CESAM, Department of Environment and Planning, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.

PMID: 34119993
DOI: 10.1016/j.jenvman.2021.112937

Abstract

Contamination of surrounding waters with antibiotics by aquaculture effluents can be problematic due to the possible increase of bacterial resistance, making it crucial the efficient treatment of those effluents before their release into the environment. In this work, the application of waste-based magnetic biochar/titanium dioxide (BC/TiO₂) composite materials on the photodegradation of two antibiotics widely used in aquaculture (sulfadiazine (SDZ) and oxolinic acid (OXA)) was assessed. Four materials were synthesized: BCMag (magnetized BC), BCMag_TiO₂ (BCMag functionalized with TiO₂), BC_TiO₂_MagIn and BC_TiO₂_MagEx (BC functionalized with TiO₂ and afterwards magnetized by in-situ and ex-situ approaches, respectively). SDZ half-life time (t_1/2) noticeably decreased 3.9 and 3.4 times in presence of BCMag_TiO₂ and BC_TiO₂_MagEx, respectively. In the case of OXA, even though differences were not so substantial, the produced photocatalysts also allowed for a decrease in t_1/2 (2.6 and 1.7 times, in presence of BCMag_TiO₂ and BC_TiO₂_MagEx, respectively). Overall, the here synthesized BC/TiO₂ magnetic nanocomposites through a circular economy process are promising photocatalysts for a sustainable solar-driven removal of antibiotics from aquaculture effluents.

Keywords: Carbonaceous nanocomposites; Photodegradation; Synthetic photocatalysts; Waste valorization; Water treatment.

MeSH terms

Anti-Bacterial Agents*
Aquaculture
Catalysis
Charcoal
Nanocomposites*
Sunlight
Titanium

Substances

Anti-Bacterial Agents
biochar
titanium dioxide
Charcoal
Titanium