abstract
The rampant use of plastics, with the potential to degrade into insidious microplastics (MPs), poses a significant threat by contaminating aquatic environments. In the present study, we delved into the analysis of effluents from textile industries, a recognized major source of MPs contamination. Data were further discussed and compared with a municipal wastewater treatment plant (WWTP) effluent. All effluent samples were collected at the final stage of treatment in their respective WWTP. Laser diffraction spectroscopy was used to evaluate MP dimensions, while optical and fluorescence microscopies were used for morphology analysis and the identification of predominant plastic types, respectively. Electrophoresis was employed to unravel the prevalence of negative surface charge on these plastic microparticles. The analysis revealed that polyethylene terephthalate (PET) and polyamide were the dominant compounds in textile effluents, with PET being predominant in municipal WWTP effluents. Surprisingly, despite the municipal WWTP exhibiting higher efficiency in MP removal (ca. 71% compared to ca. 55% in textile industries), it contributed more to overall pollution. A novel bio-based flocculant, a cationic cellulose derivative derived from wood wastes, was developed as a proof-of-concept for MP flocculation. The novel derivatives were found to efficiently flocculate PET MPs, thus allowing their facile removal from aqueous media, and reducing the threat of MP contamination from effluents discharged from WWTPs.
keywords
WATER TREATMENT PLANTS; POLYETHYLENE; OXIDATION; ELECTRON
subject category
Polymer Science
authors
Magalhaes, S; Paciência, D; Rodrigues, JMM; Lindman, B; Alves, L; Medronho, B; Rasteiro, MD
our authors
João M. M. Rodrigues
Assistant Researcheracknowledgements
This work was financially supported by the Portuguese Foundation for Science and Technology (FCT), through the PhD grant 2020.07638.BD (DOI: https://doi.org/10.54499/2020.07638.BD). B.M., L.A., and J.M.M.R. also acknowledge FCT for the individual research contracts CEECIND/01014/2018 (DOI: 10.54499/CEECIND/01014/2018/CP1540/CT0002), 2021.00399.CEECIND (DOI: (https://doi.org/10.54499/2021.00399.CEECIND/CP1656/CT0025)), and CEECIND/01363/2018 (DOI: 10.54499/CEECIND/01363/2018/CP1559/CT0022), respectively. The MED (DOI: https://doi.org/10.54499/UIDB/05183/2020; https://doi.org/10.54499/UIDP/05183/2020) and CHANGE (https://doi.org/10.54499/LA/P/0121/2020) also acknowledge the support from FCT (UIDB/05183/2020; LA/P/0121/2020). This work was supported by national funds from FCT-Fundacao para a Ciencia e a Tecnologia, I.P., within the projects 10.54499/UIDB/00102/2020 and 10.54499/UIDP/00102/2020. The NMR spectrometers were part of the National NMR Network (PTNMR) and were partially supported by Infrastructure Project N degrees 022161 (co-financed by FEDER through COMPETE 2020, POCI and PORL, and FCT through PIDDAC). Bruno Tavares and Olivia Gomes are acknowledged for inspiring suggestions.