abstract
Microplastics (MPs) pollution has become one of our time's most consequential issue. These micropolymeric particles are ubiquitously distributed across all natural and urban ecosystems. Current filtration systems in wastewater treatment plants (WWTPs) rely on non-biodegradable fossil-based polymeric filters whose mainte-nance procedures are environmentally damaging and unsustainable. Following the need to develop sustainable filtration frameworks for MPs water removal, years of R&D lead to the conception of bacterial cellulose (BC) biopolymers. These bacterial-based naturally secreted polymers display unique features for biotechnological applications, such as straightforward production, large surface areas, nanoporous structures, biodegradability, and utilitarian circularity. Diligently, techniques such as flow cytometry, scanning electron microscopy and fluorescence microscopy were used to evaluate the feasibility and characterise the removal dynamics of highly concentrated MPs-polluted water by BC biopolymers. Results show that BC biopolymers display removal effi-ciencies of MPs of up to 99%, maintaining high performance for several continuous cycles. The polymer's characterisation showed that MPs were both adsorbed and incorporated in the 3D nanofibrillar network. The use of more economically-and logistics-favourable dried BC biopolymers preserves their physicochemical properties while maintaining high efficiency (93-96%). These polymers exhibited exceptional structural preservation, conserving a high water uptake capacity which drives microparticle retention. In sum, this study provides clear evidence that BC biopolymers are high performing, multifaceted and genuinely sustainable/circular alternatives to synthetic water treatment MPs-removal technologies.
keywords
TREATMENT PLANTS; MEMBRANE BIOREACTORS; AQUATIC ENVIRONMENTS; GUT MICROBIOTA; WASTE; BIOSYNTHESIS; DEGRADATION; COMPOSITES; METABOLISM; STRAINS
subject category
Engineering; Environmental Sciences & Ecology; Water Resources
authors
Faria, M; Cunha, C; Gomes, M; Mendonca, I; Kaufmann, M; Ferreira, A; Cordeiro, N
our authors
Artur Jorge Faria Ferreira
Professor Coordinatoracknowledgements
This research was supported by Foundation for Science and Technology (FCT), through CIIMAR -UIDB/04423/2020 and UIDP/04423/2020, and by the European Territorial Cooperation Programme PCT -MAC 2014-2020 through REBECA-CCT (MAC/1.1.B/269) project. Marisa Faria was financially supported by a doctoral grant (BD/6615/2020) from FCT. Ivana Mendonca acknowledges a research grant financed by Fundacao Amadeu Dias under the scope of the programme BYT+, promoted by CIIMAR.