Vendredi 27 Septembre 2019 à 15h
Salle de réunion du 1er étage
Séminaire du Docteur Ludovic DUMEE
ARC DECRA Senior Research Fellow
Institute for Frontier Materials | Deakin University
“Microplastics – threats and challenges during waste water processing”
Abstract:
Microplastics represent a great challenge for both fresh and saline water sources, affecting aquatic life forms, aquafarming operations and the drinkability of water for human consumption. Levels of contaminations are unprecedented and challenges in the detection, quantification and assessment of the impact of such contaminants on the food chain, remain unclear. The mechanical and chemical breakdown of plastic litter increases the release of nano- and micro- plastics that can foul membranes during filtration processes thus reducing their performance.
In this work, the potential fragmentation of microplastics extracted from cosmetic products in nanoscale dimension plastics will first be discussed in light of mild shear forces relevant to waste water treatment processes. The extent of fouling of these nano/microplastics across commercial ultrafiltration poly(sulfone) membrane, with size distributions ranging from 13 to 690 nm, was investigated. The cross-flow filtration of the plastic particles over 48 h at a 1 bar pressure reduced the permeate water flux by 38 % compared to pure water filtration. Over 30 % of the nano- and micro- plastics initially present in the feed were absorbed onto the membrane surface within the 48 h of filtration. Particulate fouling mechanism was sequentially modelled into intermediate and complete pore blockage, followed by cake layer formation. Hydrophobic interactions and surface repulsion forces were found to dictate the adsorption rate of the nano- and micro- plastics onto the membrane surface.
