Concentration polarization over reverse osmosis membranes with engineered surface features

Zhou, Zuo; Ling, Bowen; Battiato, Ilenia; Husson, Scott M.; Ladner, David A.

doi:10.1016/j.memsci.2020.118199

Cited by 53 publications

(40 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Multiple membrane models with line-and-groove surface patterns were built for analysis. Details of the developed model were explained elsewhere [ 22 ]. Table 2 summarizes the parameters of the four geometries (four stamps) that were studied.…”

Section: Methodsmentioning

confidence: 99%

“…Equation (1) is the Navier–Stokes equation that is used to describe the motion of the fluid, and Equation (2) is the continuity equation. Details of the modeling conditions were described elsewhere [ 22 ].

…”

Section: Methodsmentioning

confidence: 99%

“…Jang et al [ 21 ] studied both nanometer-and micrometer-scale patterns achieved through nanoimprint lithography. Zhou et al [ 22 ] investigated several line-and-groove patterns, rectangular and circular pillars, and pyramids within the nanometer- to micrometer-scale range. Ling et al [ 23 ] studied microscale pillars on RO membranes.…”

Section: Introductionmentioning

confidence: 99%

“…In our case, these low-shear regions occur within the pattern grooves, which delays cake layer formation and leads to higher values of threshold flux. Based on that work, we theorized that the pattern geometry would affect the threshold flux by altering the shear stress profiles at the interface, as we have seen in computational simulation work [ 22 ].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Understanding the Role of Pattern Geometry on Nanofiltration Threshold Flux

et al. 2020

Self Cite

View full text Add to dashboard Cite

Colloidal fouling can be mitigated by membrane surface patterning. This contribution identifies the effect of different pattern geometries on fouling behavior. Nanoscale line-and-groove patterns with different feature sizes were applied by thermal embossing on commercial nanofiltration membranes. Threshold flux values of as-received, pressed, and patterned membranes were determined using constant flux, cross-flow filtration experiments. A previously derived combined intermediate pore blocking and cake filtration model was applied to the experimental data to determine threshold flux values. The threshold fluxes of all patterned membranes were higher than the as-received and pressed membranes. The pattern fraction ratio (PFR), defined as the quotient of line width and groove width, was used to analyze the relationship between threshold flux and pattern geometry quantitatively. Experimental work combined with computational fluid dynamics simulations showed that increasing the PFR leads to higher threshold flux. As the PFR increases, the percentage of vortex-forming area within the pattern grooves increases, and vortex-induced shielding increases. This study suggests that the PFR should be higher than 1 to produce patterned membranes with maximal threshold flux values. Knowledge generated in this study can be applied to other feature types to design patterned membranes for improved control over colloidal fouling.

show abstract

Section: Methodsmentioning

confidence: 99%

…”

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Understanding the Role of Pattern Geometry on Nanofiltration Threshold Flux

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…Membrane fouling and concentration polarization are among main obstacles that are challenging ultimate process efficiency, besides increasing energy demands and operation costs [3]. Simulations and lab-scale experiments have shown that manipulating membrane surface topography by introducing certain nano-or microstructures can potentially modify fluid characteristics and shear stress toward better antifouling behavior and less tendency for concentration polarization, without significantly increasing the pressure drop in the feed/retentate channel [4][5][6][7]. Nevertheless, such effects are critically influenced by the pattern design and dimensions, operating conditions, and characteristics of solute and/or foulants [8][9][10].…”

Section: Introductionmentioning

confidence: 99%

Studying Fluid Characteristics Atop Surface Patterned Membranes via Particle Image Velocimetry

Denizer

ElSherbiny

Ulbricht

et al. 2021

Chemie Ingenieur Technik

View full text Add to dashboard Cite

Surface patterning is a recent promising approach to promote performance of pressure-driven membranes in water treatment and desalination. Nevertheless, knowledge about foulant deposition mechanisms, especially at early stage of filtration, is still lacking. The applicability of particle imaging velocimetry to study fluid characteristics atop surface patterned thin-film composite membranes was investigated at different operating conditions. This work is an important first step toward reliable understanding of the impacts of topographical membrane surface modification on hydrodynamic conditions and foulant deposition mechanisms.

show abstract

Concentration polarization on surface patterned membranes

et al. 2022

View full text Add to dashboard Cite

Surface pattern is a promising approach to enhance membrane performance while contradictory results have been reported on its impact on concentration polarization.Here, we provide an experimental and modeling study of the concentration polarization on patterned membranes by varying pattern size, solute size, surface hydrophilicity, and membrane orientation. Interesting trends were observed when comparing different membrane orientations, where relative concentration polarization degree (CPD) was found depend on molecular weight. Salts and small organic molecules encountered more severe CPD in the transverse mode, while molecules larger than a threshold value showed a different trend. Such threshold molecular weight increased at larger pattern size. Simulation results were consistent with experimental observations, and revealed the critical role of diffusivity on such phenomena. Results also showed more severe concentration polarization on patterned membranes in both parallel and transverse modes in most cases, compared to smooth membrane.

show abstract

Concentration polarization over reverse osmosis membranes with engineered surface features

Cited by 53 publications

References 28 publications

Understanding the Role of Pattern Geometry on Nanofiltration Threshold Flux

Understanding the Role of Pattern Geometry on Nanofiltration Threshold Flux

Studying Fluid Characteristics Atop Surface Patterned Membranes via Particle Image Velocimetry

Concentration polarization on surface patterned membranes

Contact Info

Product

Resources

About