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 (t1/2) 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 t1/2 (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
OXOLINIC ACID; DEGRADATION; PHOTODEGRADATION; TIO2; SULFAMETHOXAZOLE; CARBAMAZEPINE; ADSORBENTS; ADSORPTION; COMPOSITE; WATER
subject category
Environmental Sciences
authors
Silva, CP; Pereira, D; Calisto, V; Martins, MA; Otero, M; Esteves, VI; Lima, DLD
our authors
Manuel António Martins da Silva
Researcheracknowledgements
This work was funded by FEDER through CENTRO 2020 and by national funds through Fundacao para a Ciencia e a Tecnologia, I.P. (FCT) within the research project REM-AQUA (PTDC/ASP-PES/29021/2017) . Also, this work is a contribution to the project WasteMAC (POCI-01-0145-FEDER-028598) funded by FCT, through national funds, and the co-funding by FEDER, within the PT2020 Partnership Agreement and Compete 2020. Diana Lima was funded by national funds (OE) , through FCT, in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. Marta Otero and Diogo Pereira thank support by FCT Investigator Program (IF/00314/2015) . Vania Calisto is also thankful to FCT for the Scientific Employment Stimulus support (CEECIND/00007/2017) . Thanks are due, for the financial support to CESAM (UIDB/50017/2020+UIDP/50017/2020) , to FCT/MCTES through national funds.