Impact of operation conditions, foulant adsorption, and chemical cleaning on the nanomechanical properties of ultrafiltration hollow fiber membranes
MetadataShow full item record
This study analyzed the change in nanomechanical properties of ultrafiltration hollow fiber membranes harvested from pilot-scale units after twelve months of operation. Quantitative Nanomechanical Mapping technique was used to distinguish between adhesion, dissipation, deformation, and modulus while simultaneously generating a topographic image of membranes. Nanomechanical maps of virgin membranes evidenced surfaces of heterogeneous properties and were described by probability density functions. Operating conditions and feed quality exerted an impact on membranes. Clean harvested membranes showed a higher mean modulus and dissipation, and a lower deformation than virgin membranes, indicating stiffer membranes of lower elastic deformation. A significant fraction of these measurements displayed peak values deviating from the distribution; which represents regions of the membrane with properties highly differing from the probability density function. The membrane polymeric material experienced severe physicochemical changes by foulant adsorption and reaction with cleaning agents. Foulant adsorption on membranes was heterogeneous in both morphology and mechanical properties and could not be statistically described. Foulants, i.e., mainly consisting of polysaccharides and proteinaceous structures, displayed low elastic deformation and high roughness and adhesion. The presence of foulants after chemical cleaning and their high adhesion would be a direct nanoscale evidence of irreversible fouling. By the end of the operation, the Trans-Membrane Pressure experienced a 40% increase. The cleaning process was not able to fully recover the initial TMP, indicating irreversible fouling, i.e., permanent change in membrane characteristics and decrease in performance. These results suggest a link between the macroscopic properties and nanomechanical characteristics of membranes. This study advances our nanoscale understanding of the impact of fouling and operating conditions on membranes characteristics.
Showing items related by title, author, creator and subject.
Nanomechanical characterization of recalcitrant foulants and hollow fibemembranes in ultrafiltration systemsGutierrez, L.; Keucken, A.; Aubry, C.; San Martin, T.; Croue, Jean-Philippe (2018)Long-term nanomechanical changes of polymeric ultrafiltration (UF) membranes caused by fouling/cleaning agents in water treatment are not well established in the literature. The goal of this study was to investigate the ...
Lu, X.; Peng, Y.; Ge, L.; Lin, R.; Zhu, Z.; Liu, Shaomin (2016)© 2015 Elsevier B.V. This study aimed to develop an effective method to fabricate the amphiphobic polyvinylidene fluoride (PVDF) composite membranes for membrane distillation (MD) with excellent tolerance to various organic ...
Ceramic membrane as a pretreatment for reverse osmosis: Interaction between marine organic matter and metal oxidesDramas, L.; Croue, Jean-Philippe (2013)Scaling and (bio)fouling phenomena can severely alter the performance of the reverse osmosis process during desalination of seawater. Pretreatments must be applied to efficiently remove particles, colloids, and also ...