abstract
Microfibers (MFs), the dominant form of microplastics in ecosystems, pose a significant environmental risk due to the inadequacy of existing wastewater treatments to remove them. Recognising the need to develop sustainable solutions to tackle this environmental challenge, this research aimed to find an eco-friendly solution to the pervasive problem of MFs contaminating water bodies. Unused remnants of bacterial cellulose (BC) were ground to form a hydrogel-form of bacterial cellulose (BCH) and used as a potential bioflocculant for polyacrylonitrile MFs. The flocculation efficiency was evaluated across various operational and environmental factors, employing response surface methodology computational modelling to elucidate and model their impact on the process. The results revealed that the BCH:MFs ratio and mixing intensity were key factors in flocculation efficiency, with BCH resilient across a range of environmental conditions, achieving a 93.6 % average removal rate. The BCH's strong retention of MFs released only 8.3 % of the MFs, after a 24 -hour wash, and the flocculation tests in contaminated wastewater and chlorinated water yielded 89.3 % and 86.1 % efficiency, respectively. Therefore, BCH presents a viable, sustainable, and effective approach for removing MFs from MFs-contaminated water, exhibiting exceptional flocculation performance and adaptability. This pioneer study using BCH as a bioflocculant for MFs removal sets a new standard in sustainable wastewater treatment, catalysing research on fibrous pollutant mitigation for environmental protection.
keywords
MICROPLASTICS; FIBERS; BIOFLOCCULANT; FLOCCULATION
subject category
Environmental Sciences & Ecology
authors
Rodrigues, F; Faria, M; Mendonça, I; Sousa, E; Ferreira, A; Cordeiro, N
our authors
Artur Jorge Faria Ferreira
Professor Coordinatoracknowledgements
This research was supported by the European Territorial Cooperation Programme PCT-MAC 2014-2020 through REBECA-CCT (MAC/1.1.B/ 269) project. CIIMAR was supported by the Foundation for Science and Technology (FCT), through UIDB/04423/2020 and UIDP/04423/2020 funds. Marisa Faria and Ivana mendonca were financially supported by a doctoral grant (BD/6615/2020 and 2023.04389.BD, respectively) from FCT.