Filtration performance and pore size distribution of hypochlorite aged PES/PVP ultrafiltration membranes

Pellegrin, Bastien; Mezzari, Fernanda; Hanafi, Yamina; Szymczyk, Anthony; Rémigy, Jean-Christophe; Causserand, Christel

doi:10.1016/j.memsci.2014.09.028

Cited by 57 publications

(31 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Membrane samples were dried under dynamic vacuum for 2 days before being introduced in the ultra-high vacuum chamber and kept at 10 -6 Pa several hours before XPS analysis. The increase in the pure water permeability of PES/PVP membranes after exposure to bleach solutions was already reported by some authors [2,39] and was attributed to the porous structure modification of membranes as a result of partial removal of PVP. Wolff and Zydney observed similar results with PSf/PVP membranes and noticed that the membrane permeability still increased even after complete removal of PVP, thus indicating chemical degradation of PSf itself [40].…”

Section: Membrane Characterizationsupporting

confidence: 66%

Electrokinetic analysis of PES/PVP membranes aged by sodium hypochlorite solutions at different pH

Hanafi

Loulergue

Ababou‐Girard

et al. 2016

Journal of Membrane Science

Self Cite

View full text Add to dashboard Cite

International audienceThis study focused on the impact of ageing solution pH (200 ppm TFC sodium hypochlorite) on the electrokinetic properties of a commercial PES/PVP UF membrane. PVP oxidation, leading to an increase in the negative charge density of aged membranes, was pointed out whatever the ageing solution pH although different mechanisms might be involved depending on the ageing pH. PES degradation was also demonstrated. Electrokinetic measurements highlighted the formation of functional groups with very weak acid properties on the surface of membranes aged in sodium hypochlorite at pH 8.0 and to a lesser extent at pH 6.0 and 11.5. These results were found to be consistent with the formation of phenol groups due to the radical hydroxylation of PES aromatic rings. Moreover, the disappearance of the isoelectric point of membranes aged in sodium hypochlorite at pH 6.0 and 8.0 gave evidence for the formation of strong acid groups such as sulfonic acids. These results suggested some PES-chain scissions, which was confirmed by XPS measurements. The disappearance of the isoelectric point was not observed for membranes aged in sodium hypochlorite at pH 11.5, thus indicating that ClO− was not involved in PES-chain scissions for the ageing conditions considered in this work. Finally, electrokinetic measurements performed with the addition of tertiobutanol (free radical scavenger) and thermo-oxidation experiments revealed for the first time that, although both HClO and free radicals species contributed to PES-chain scissions, HClO had the greater impact on PES degradation

show abstract

Section: Membrane Characterizationsupporting

confidence: 66%

Electrokinetic analysis of PES/PVP membranes aged by sodium hypochlorite solutions at different pH

Hanafi

Loulergue

Ababou‐Girard

et al. 2016

Journal of Membrane Science

Self Cite

View full text Add to dashboard Cite

show abstract

“…Spectra were collected from 600 to 3700 cm -1 at 2 cm -1 resolution and each spectrum was averaged from 128 scans after background recording performed at ambient air. 12 …”

Section: Atr-ftir Spectroscopymentioning

confidence: 99%

“…Sodium hypochlorite is one of the most widely-used disinfecting/cleaning agents owing to its high efficiency and low cost [8][9][10]. However, it is well known that sodium hypochlorite has a strong impact on membranes properties such as structure [2,11,12], surface charge [2,13,14] and chemical composition [3,10,13,15], which directly impacts their filtration performance and their mechanical strength as well [3,15,16].…”

Section: Introductionmentioning

confidence: 99%

Influence of PVP content on degradation of PES/PVP membranes: Insights from characterization of membranes with controlled composition

Kourde-Hanafi

Loulergue

Szymczyk

et al. 2017

Journal of Membrane Science

Self Cite

View full text Add to dashboard Cite

Sodium hypochlorite is widely used to clean/sanitize PES/PVP membranes. However, this strong oxidant is responsible for accelerated polymer ageing, thus impairing PES/PVP membrane lifespan. This work aimed at getting a better understanding of the role of PVP in the degradation of PES/PVP membranes. As the precise chemical composition of commercial membranes is most often unknown, PES/PVP membranes with various PVP to PES ratios (from 0 to 44 wt %) were synthesized and aged dynamically by filtering sodium hypochlorite solutions. PVP oxidization and partial disappearance from the membrane matrix was observed whatever the membrane composition. Moreover, PES-chain scissions were put in evidence even for pure PES membranes, thus highlighting that PES degradation was not systematically related to the presence of PVP. Conversely, PES hydroxylation was observed only for membranes containing PVP, the hydroxylation rate being dependent on the PVP content. Interestingly, the occurrence of PES-chain scissions impacted the membrane

show abstract

“…The enhancement in membrane hydrophilicity could be related to the presence of the hydrophilic PVP into the polymeric matrix and not washed away during membrane post-treatment with water [29][30][31]. The water permeability is reported in Table 2.…”

Section: Membrane Characterizationmentioning

confidence: 99%

Functional Properties of Punica granatum L. Juice Clarified by Hollow Fiber Membranes

et al. 2016

View full text Add to dashboard Cite

Abstract:There is currently much interest in pomegranate juice because of the high content of phenolic compounds. Moreover, the interest in the separation of bioactive compounds from natural sources has remarkably grown. In this work, for the first time, the Punica granatum L. (pomegranate) juice-clarified by using polyvinylidene fluoride (PVDF) and polysulfone (PSU) hollow fiber (HF) membranes prepared in the laboratory-was screened for its antioxidant properties by using different in vitro assays, namely 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), Ferric Reducing Antioxidant Power (FRAP), and β-carotene bleaching tests, and for its potential inhibitory activity of the carbohydrate-hydrolysing enzymes, α-amylase and α-glucosidase. The effects of clarification on quality characteristics of the juice were also investigated in terms of total phenols, flavonoids, anthocyanins, and ascorbic acid. Experimental results indicated that PVDF membranes presented a lower retention towards healthy phytochemicals in comparison to PSU membranes. Accordingly, the juice clarified with PVDF membranes showed the best antioxidant activity. Moreover, the treatment with PVDF membranes produced a clarified juice with 2.9-times fold higher α-amylase inhibitory activity in comparison to PSU (IC 50 value of 75.86 vs. 221.31 µg/mL, respectively). The same trend was observed using an α-glucosidase inhibition test. These results highlight the great potential of the clarified juice as a source of functional constituents.

show abstract

Filtration performance and pore size distribution of hypochlorite aged PES/PVP ultrafiltration membranes

Cited by 57 publications

References 25 publications

Electrokinetic analysis of PES/PVP membranes aged by sodium hypochlorite solutions at different pH

Electrokinetic analysis of PES/PVP membranes aged by sodium hypochlorite solutions at different pH

Influence of PVP content on degradation of PES/PVP membranes: Insights from characterization of membranes with controlled composition

Functional Properties of Punica granatum L. Juice Clarified by Hollow Fiber Membranes

Contact Info

Product

Resources

About