On the long-term pH stability of polyelectrolyte multilayer nanofiltration membranes

Elshof, Maria G.; Vos, Wiebe M. de; Grooth, Joris de; Benes, Nieck E.

doi:10.1016/j.memsci.2020.118532

Cited by 83 publications

(56 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The compositions of the feed, the permeate, and the retentate were determined using gel permeation chromatography (GPC, Agilent Technologies 1200/1260 Infinity GPC/SEC series) according to a previously described protocol. 23 The PEG retention was then calculated using eq 2 and the MWCO was determined as the molar mass that is retained for 90% or more. Also here, three samples were tested ( N = 3) and the 95% confidence interval was calculated.…”

Section: Methodsmentioning

confidence: 99%

Poly(aryl cyanurate)-Based Thin-Film Composite Nanofiltration Membranes

Elshof

Maaskant

Hempenius

et al. 2021

ACS Appl. Polym. Mater.

Self Cite

View full text Add to dashboard Cite

The successful synthesis of poly(aryl cyanurate) nanofiltration membranes via the interfacial polymerization reaction between cyanuric chloride and 1,1,1-tris(4-hydroxyphenyl)ethane (TPE), atop a polyethersulfone ultrafiltration support, is demonstrated. The use of cyanuric chloride allows for the formation of a polymer that does not contain hydrolysis-susceptible amide bonds that inherently limit the stability of polyamide nanofiltration membranes. In order to achieve a thin defect-free cross-linked film via interfacial polymerization, a sufficient number of each monomer should react. However, the reactivities of the second and third chloride groups of the cyanuric chloride are moderate. Here, this difficulty is overcome by the high functionality and the high reactivity of TPE. The membranes demonstrate a typical nanofiltration behavior, with a molecular weight cutoff of 400 ± 83 g·mol –1 and a permeance of 1.77 ± 0.18 L·m –2 h –1 bar –1 . The following retention behavior Na 2 SO 4 (97.1%) > MgSO 4 (92.8%) > NaCl (51.3%) > MgCl 2 (32.1%) indicates that the membranes have a negative surface charge. The absence of amide bonds in the membranes was expected to result in superior pH stability as compared to polyamide membranes. However, it was found that under extremely acidic conditions (pH = 1), the performance showed a pronounced decline over the course of 2 months. Under extremely alkaline conditions (pH = 13), after 1 month, the performance was lost. After 2 months of exposure to moderate alkaline conditions (pH = 12), the MgSO 4 retention decreased by 14% and the permeance increased by 2.5-fold. This degradation was attributed to the hydrolysis of the aryl cyanurate bond that behaves like an ester bond.

show abstract

Section: Methodsmentioning

confidence: 99%

Poly(aryl cyanurate)-Based Thin-Film Composite Nanofiltration Membranes

Elshof

Maaskant

Hempenius

et al. 2021

ACS Appl. Polym. Mater.

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Resultsmentioning

confidence: 99%

“…Comparison between asymmetric LbL NF membranes (red diamonds) with other LbL NF membranes reported in literature (white diamonds) and commercial NF membranes (gray diamonds). Data points: 1-4, 9, 12, 13, 53 5, 54 6, 55 7, 14, 16, 17, 56 8, 15, 57 10, 58 11, 59 18 60 [Color figure can be viewed at wileyonlinelibrary.com] DADMAC) layers in one membrane was used. This combination resulted in the successful production of negatively charged LbL membranes with both high permeabilities and high retentions for negatively charged ions, while simultaneously reducing odd-even effects.…”

Section: F I G U R Ementioning

confidence: 99%

Asymmetric layer‐by‐layer polyelectrolyte nanofiltration membranes with tunable retention

Scheepers

Chatillon

Nijmeijer

et al. 2021

Journal of Polymer Science

View full text Add to dashboard Cite

Nanofiltration (NF) membrane processes are attractive to remove multivalent ions. As ion retention in NF membranes is determined by both size and charge exclusion, negatively charged membranes are required to reject negatively charged ions. Layer‐by‐layer assembly of alternating polycation (PC) and polyanion layers on top of a support is a versatile method to produce membranes. Especially the polyelectrolyte (PE) couple polydiallyldimethylammoniumchloride and poly(sodium‐4‐styrenesulfonate) (PDADMAC/PSS) is extensively investigated. This PE couple cannot form highly negatively charged membrane surfaces, due to interdiffusion and charge overcompensation of PDADMAC into the PSS layers, which limits the operational window to tailor membrane properties. We propose the use of asymmetric layer formation and show how combining two charge densities of one PC can produce negatively charged NF membranes. Starting from hollow fiber ultrafiltration supports coated with base layers of PDADMAC/PSS, they are coated with PDADMAC/PSS or poly(acrylamide‐co‐diallyldimethylammoniumchloride), P(AM‐co‐DADMAC)/PSS layers. P(AM‐co‐DADMAC) has a charge density of only 32% compared to 100% for PDADMAC. The particular novel membranes coated with P(AM‐co‐DADMAC) have a highly negatively charged surface and high permeabilities (7–19 L/[m2hbar]), with high retentions for Na2SO4 of up to 95%. These values position the developed membranes in the top range compared to commercial and other layer‐by‐layer membranes.

show abstract

“… 36 PEM coatings allow for a nanometer-control over the membrane active layer thickness and chemistry. 132 − 134 In particular, the availability of different polyelectrolytes as building blocks 115 , 121 as well as coating conditions (e.g., salinity 135 , 136 and pH 137 , 138 ) allow the production of thin films with engineered functionality for multiple membrane applications, such as ion selectivity, 139 fouling control, 140 stability against harsh wastewaters, 34 , 141 removal of contaminants from water, 142 , 143 and responsiveness. 144 …”

Section: Polyelectrolyte Multilayers On Porous Substratesmentioning

confidence: 99%

“… 31 The chemical stability of PECs is not restricted to organic solvents, with a good selection of PEs it is possible to obtain membranes with remarkable stability against hypochlorite 32 and extreme pH conditions. 11 , 33 , 34 …”

Section: Introductionmentioning

confidence: 99%

Polyelectrolytes as Building Blocks for Next-Generation Membranes with Advanced Functionalities

Durmaz

Şahin

Virga

et al. 2021

ACS Appl. Polym. Mater.

Self Cite

View full text Add to dashboard Cite

The global society is in a transition, where dealing with climate change and water scarcity are important challenges. More efficient separations of chemical species are essential to reduce energy consumption and to provide more reliable access to clean water. Here, membranes with advanced functionalities that go beyond standard separation properties can play a key role. This includes relevant functionalities, such as stimuli-responsiveness, fouling control, stability, specific selectivity, sustainability, and antimicrobial activity. Polyelectrolytes and their complexes are an especially promising system to provide advanced membrane functionalities. Here, we have reviewed recent work where advanced membrane properties stem directly from the material properties provided by polyelectrolytes. This work highlights the versatility of polyelectrolyte-based membrane modifications, where polyelectrolytes are not only applied as single layers, including brushes, but also as more complex polyelectrolyte multilayers on both porous membrane supports and dense membranes. Moreover, free-standing membranes can also be produced completely from aqueous polyelectrolyte solutions allowing much more sustainable approaches to membrane fabrication. The Review demonstrates the promise that polyelectrolytes and their complexes hold for next-generation membranes with advanced properties, while it also provides a clear outlook on the future of this promising field.

show abstract

On the long-term pH stability of polyelectrolyte multilayer nanofiltration membranes

Cited by 83 publications

References 45 publications

Poly(aryl cyanurate)-Based Thin-Film Composite Nanofiltration Membranes

Poly(aryl cyanurate)-Based Thin-Film Composite Nanofiltration Membranes

Asymmetric layer‐by‐layer polyelectrolyte nanofiltration membranes with tunable retention

Polyelectrolytes as Building Blocks for Next-Generation Membranes with Advanced Functionalities

Contact Info

Product

Resources

About