Effect of salinity and nanoparticle polydispersity on retention and UF membrane fouling

Morgane Le Hir (1) , Y. Wyart (1) , Gaelle Georges (2) , Laure Siozade (2) , Patrick Sauvade (3) , Philippe Moulin (1)

1 M2P2 - Laboratoire de Mécanique, Modélisation et Procédés Propres
2 DiMABio - DiMABio
3 Aquasource - Aquasource

Nanoparticles (NPs) retention by ultrafiltration (UF) membrane presents a great interest since few decades due to the emergence of this new pollution in natural waters used to produce drinking water. Some studies already showed that specific NPs are efficiently retained by UF (Troester et al. 2016). However, this retention is strongly dependent of water composition and chemistry. Presence of salts can affect the stability of NPs suspensions and lead to aggregation or repulsion phenomenon which can induce a modification of NP retention. In this study, the NP retention have been studied with the filtration of NP suspension with size close to or smaller than membrane pore size. The influence of salinity and polydispersity of the feed suspensions on NP retention was analyzed and compared to simplified NP suspension. To deepen this work, the location of membrane fouling after filtration experiment was determined by Confocal Laser Scanning Microscopy (CLSM). This location of the fluorescent signal allowed to identify the membrane retention zone(s), to estimate fouling mechanisms operating during the filtration and to determine the penetration profile. Moreover, it is possible to distinguish the fouling contribution of each size of NP with or without salt. Microscopic observations were compared to fouling mechanisms found with application of Hermia models on flux data observed during the experiment.

Mots clés: Ultrafiltration; nanoparticles; fouling; fluorescence; polydispersity; salinity

Domaines: Génie des procédés

Morgane Le Hir, Y. Wyart, Gaelle Georges, Laure Siozade, Patrick Sauvade, et al.. Effect of salinity and nanoparticle polydispersity on retention and UF membrane fouling. Euromembrane 2018, Jul 2018, Valence, Spain. ⟨hal-02116751⟩