1. Detoxification of Ciprofloxacin in an Anaerobic Bioprocess Supplemented with Magnetic Carbon Nanotubes: Contribution of Adsorption and Biodegradation Mechanisms
- Author
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M. Fernando R. Pereira, O. Salomé G. P. Soares, Luciana Pereira, Ana Júlia Cavaleiro, Ana Rita Silva, Andreia Filipa Ferreira Salvador, Cátia Sofia Neves Braga, M. Madalena Alves, and Universidade do Minho
- Subjects
Redox mediators ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,law.invention ,lcsh:Chemistry ,Methanospirillum ,Bioreactors ,law ,Ciprofloxacin ,Anaerobiosis ,Magnetite Nanoparticles ,lcsh:QH301-705.5 ,Spectroscopy ,chemistry.chemical_classification ,Sewage ,Chemistry ,General Medicine ,021001 nanoscience & nanotechnology ,Aliivibrio fischeri ,3. Good health ,Computer Science Applications ,redox mediators ,Biodegradation, Environmental ,Anaerobic reduction ,0210 nano-technology ,Oxidation-Reduction ,anaerobic reduction ,Magnetic carbon nanotubes ,Electrons ,Carbon nanotube ,Microbial Sensitivity Tests ,Methanobrevibacter ,Redox ,Catalysis ,Article ,Inorganic Chemistry ,Adsorption ,ciprofloxacin ,Bioreactor ,Humans ,Organic matter ,Physical and Theoretical Chemistry ,Bioprocess ,magnetic carbon nanotubes ,Molecular Biology ,0105 earth and related environmental sciences ,Science & Technology ,Toxicity ,Nanotubes, Carbon ,Organic Chemistry ,Methanobacterium ,toxicity ,Biodegradation ,Methanosarcinales ,Chemical engineering ,lcsh:Biology (General) ,lcsh:QD1-999 ,adsorption ,Water Pollutants, Chemical - Abstract
In anaerobic bioreactors, the electrons produced during the oxidation of organic matter can potentially be used for the biological reduction of pharmaceuticals in wastewaters. Common electron transfer limitations benefit from the acceleration of reactions through utilization of redox mediators (RM). This work explores the potential of carbon nanomaterials (CNM) as RM on the anaerobic removal of ciprofloxacin (CIP). Pristine and tailored carbon nanotubes (CNT) were first tested for chemical reduction of CIP, and pristine CNT was found as the best material, so it was further utilized in biological anaerobic assays with anaerobic granular sludge (GS). In addition, magnetic CNT were prepared and also tested in biological assays, as they are easier to be recovered and reused. In biological tests with CNM, approximately 99% CIP removal was achieved, and the reaction rates increased ?1.5-fold relatively to the control without CNM. In these experiments, CIP adsorption onto GS and CNM was above 90%. Despite, after applying three successive cycles of CIP addition, the catalytic properties of magnetic CNT were maintained while adsorption decreased to 29 ± 3.2%, as the result of CNM overload by CIP. The results suggest the combined occurrence of different mechanisms for CIP removal: adsorption on GS and/or CNM, and biological reduction or oxidation, which can be accelerated by the presence of CNM. After biological treatment with CNM, toxicity towards Vibrio fischeri was evaluated, resulting in ? 46% detoxification of CIP solution, showing the advantages of combining biological treatment with CNM for CIP removal., This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020-Programa Operacional Regional do Norte. Ana Rita Silva holds an FCT grant SFRH/BD/131905/2017. Cátia S.N. Braga holds an FCT grant SFRH/BD/132003/2017. This work was also financially supported by: Base Funding-UIDB/50020/2020 of the Associate Laboratory LSRE LCM-funded by national funds through FCT/MCTES (PIDDAC). OSGPS acknowledges FCT fund ing under the Scientific Employment Stimulus-Institutional Call CEECINST/00049/2, info:eu-repo/semantics/publishedVersion
- Published
- 2021