scholarly journals Zwitterionic Polysulfone Copolymer/Polysulfone Blended Ultrafiltration Membranes with Excellent Thermostability and Antifouling Properties

Membranes ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 932
Author(s):  
Dalong Li ◽  
Changlu Gao ◽  
Xinyue Wang ◽  
Gang Wu ◽  
Jinghua Yin ◽  
...  

Membrane fouling has been one of the most important challenges in membrane separation operations. In this study, we report a facile strategy to prepare antifouling polysulfone (PSf) UF membranes by blending amphiphilic zwitterion polysulfone-co-sulfobetaine polysulfone (PSf-co-SBPSf) copolymer. The copolymer chemical structure was characterized by 1HNMR spectroscopy. The PSf/PSf-co-SBPSf blend membranes with various zwitterionic SBPSf segment contents exhibited better surface hydrophilicity and excellent antifouling ability compared to PSf and PSf/PEG membranes. The significant increase of both porosity and water permeance indicates that the PSf-co-SBPSf has a pore-forming effect. The pure water flux and flux recovery ratio of the PSf/PSf-co-SBPSf blend membranes were both remarked to improve 286.43 L/m2h and 92.26%, while bovine serum albumin (BSA) rejection remained at a high level (97.66%). More importantly, the water flux and BSA rejection see minimal variance after heat treatment, indicating excellent thermostability. Overall, the PSf/PSf-co-SBPSf blend membranes achieved a comprehensive performance of sustainable hydrophilic, high permeation flux, and remarkable antifouling ability, thus becoming a promising candidate in high-temperature separation application.

2014 ◽  
Vol 69 (9) ◽  
Author(s):  
Kanungnuch Keawsupsak ◽  
Arisa Jaiyu ◽  
Julaluk Pannoi ◽  
Punthinee Somwongsa ◽  
Nopparat Wanthausk ◽  
...  

Biodegradable polymers have been more attractive for membrane materials, especially poly(lactic acid) (PLA) because they degrade in natural environment after use. In this study, the membranes were developed from a polymer blend of PLA and other biodegradable polymers, such as poly(butylene succinate) (PBS), poly(butylene adipate-co-terphthalate) (PBAT) and Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). The membranes were formed via nonsolvent induced phase separation process using n-methyl-2-pyrrolidone (NMP) as a solvent and water as a nonsolvent. The pure water flux and BSA rejection were tested to determine the filtration performance of membranes. The microstructures and tensile strength of membranes were characterized by field emission scanning electron microscope (FE-SEM) and universal testing machine (UTM), respectively. All of membranes appeared finger-like and sponge-like structures in cross-section, and porous structure on surface. PLA/PHBV blend membranes had pure water flux and BSA rejection as high as PLA/PBS and PLA/PBAT blend membranes. The pure water flux and BSA rejection of the blend ratio (PLA/PHBV/NMP) of 15:1:84 were 65 l/m2•h and 79%, respectively.


2014 ◽  
Vol 70 (2) ◽  
Author(s):  
H. P. Ngang ◽  
A. L. Ahmad ◽  
S. C. Low ◽  
B .S. Ooi

In the present work, polyvinylidene fluoride (PVDF) ultrafiltration (UF) membranes were prepared by diffusion induced phase separation process (DIPS). N,N’-dimethylformamide (DMF) was used as the solvent and water was used as coagulant. The effect of polyethylene glycol (PEG 2000) concentration in the casting solution on morphology and performance were investigated. The physical properties of PVDF UF membranes were characterized based on pore size distribution, scanning electron microscope (SEM) and contact angle. The permeation performance of the membranes were evaluated in term of pure water flux (PWF), relative flux reduction (RFR), flux recovery ratio (FRR), and bovine serum albumin (BSA) rejection. The pore size distribution increased with the increased in PEG 2000 concentrations, and pure water flux also increased accordingly. The PEG 2000 at concentration of 6 wt.% achieved lowest RFR (50.38%), highest FRR (84.54%) and achieved highest BSA rejection, of 94.55%. This membrane exhibited better antifouling properties as well as improved membrane performance during filtration of BSA due to the optimum pore size, hydrophilic as well as smooth surface. 


2020 ◽  
Vol 20 (9) ◽  
pp. 5951-5958
Author(s):  
Menghan Sun ◽  
Mingrui Cui ◽  
Yibo Wang ◽  
Xinfei Fan ◽  
Chengwen Song

Membrane separation is recognized to be a promising technology for addressing water crisis. Unfortunately, the emergence of membrane fouling and low removal efficiency makes it unattractive for practical application. Herein, an electrochemical multifunctional CNT/Al2O3 membrane was designed coupled multiple electrochemical functions with pore sieving, which could maintain high permeability and achieve good removal efficiency simultaneously, even for those molecules with size smaller than pore size. The multifunctional CNT/Al2O3 membrane possessing a pore size of 140 nm and pure water flux of 869.6 L · m-2 · h-1 · bar-1 was prepared. The results show that the multifunctional CNT/Al2O3 membrane exhibited a good anti-fouling properties for both bio-fouling and chemical fouling under electrochemical assistance with a permeability 3.6 and 1.5 times higher than those of CNT/Al2O3 membrane alone for the treatment of E. coli and humic acid, respectively. In addition, the CNT/Al2O3 membrane with electrochemical assistance also shows a high removal efficiency for the treatment of perfluorooctane sulphonate (PFOS) and phenol whose sizes are smaller than pore size. As for the treatment of surface water, it also presented a good performance. Finally, the regeneration of the membrane was investigated and the fouled membrane was reused through an electrochemical assisted back-wash method.


Membranes ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 66 ◽  
Author(s):  
Yuandong Jia ◽  
Shuangqing Sun ◽  
Shunshun Li ◽  
Zhikun Wang ◽  
Fushan Wen ◽  
...  

Ultrafiltration (UF) membranes have found great application in sewage purification and desalination due to their high permeation flux and high rejection rate for contaminants under low-pressure conditions, but the flux and antifouling ability of UF membranes needs to be improved. Tetrakis (4-carboxyphenyl) porphyrin (TCPP) has good hydrophilicity, and it is protonated under strongly acidic conditions and then forms strong hydrogen bonds with N, O and S, so that the TCPP would be well anchored in the membrane. In this work, NaHCO3 was used to dissolve TCPP and TMC (trimesoyl chloride) was used to produce a strong acid. Then, TCPP was modified in a membrane with a different rejection rate by a method similar to interfacial polymerization. Performance tests of TCPP/polysulfone (PSf) membranes show that for the membrane with a high BSA (bovine serum albumin) rejection, when the ratio of NaHCO3 to TCPP is 16:1 (wt.%), the pure water flux of membrane Z1 16:1 is increased by 34% (from 455 to 614 Lm−2h−1bar−1) while the membrane retention was maintained above 95%. As for the membrane with a low BSA rejection, when the ratio of NaHCO3 to TCPP was 32:1, the rejection of membrane B2 32:1 was found to increase from 81% to 96%. Although the flux of membrane B2 32:1 decreased, it remained at 638 Lm−2h−1bar−1, which is comparable to the reported polymer ultrafiltration membrane. The above dual results are thought to be attributed to the synergistic effect of protonated TCPP and NaHCO3, where the former increases membrane flux and the latter increases the membrane rejection rate. This work provides a way for the application of porphyrin and porphyrin framework materials in membrane separation.


2014 ◽  
Vol 931-932 ◽  
pp. 168-172 ◽  
Author(s):  
Asmadi Ali ◽  
Mohamad Awang ◽  
Ramli Mat ◽  
Anwar Johari ◽  
Mohd Johari Kamaruddin ◽  
...  

It is well known that membrane with hydrophobic property is a fouling membrane. Polysulfone (PSf) membrane has hydrophobic characteristic was blended with a hydrophilic polymer, cellulose acetate phthalate (CAP) in order to increase hydrophilicity property of pure PSf membrane. In this study, membrane casting solutions containing 17 wt% of polymer was prepared via wet phase inversion process. The pure PSf membrane was coded as PC-0. PSf/CAP blend membranes with blend composition of 95/5, 90/10, 85/15 and 80/20 wt% of total polymer concentration in the membrane casting solutions were marked as PC-5, PC-10, PC-15 and PC-20 respectively. All of the membranes were characterized in terms of pure water flux and permeability coefficient in order to study their hydrophilicity properties. The investigated results shows that increased of CAP composition in PSf blend membranes has increased pure water flux, permeability coefficient and porosity of the blend membrane which in turn formed membrane with anti-fouling property.


Author(s):  
Xiaozheng Bian ◽  
Jianping Huang ◽  
Lin Qiu ◽  
Chunyan Ma ◽  
Danli Xi

Abstract A new type of polyvinylidene fluoride (PVDF)/polymethyl methacrylate (PMMA) hollow fiber membrane (HFM) with five bores was prepared. The effects of Polyvinylpyrrolidone (PVP), β-cyclodextrine (β-CD), Polyethylene Glycol (PEG) and Polysorbate 80 (Tween 80) and their combinations on the PVDF/PMMA five-bore HFMs were investigated. The performance and fouling characteristics of five-bore HFMs for dyeing wastewater treatment were evaluated. Results indicated that adding 5wt.% PVP could increase the porosity and water flux of the membrane but decrease the bovine serum albumin (BSA) rejection rate. Adding 5wt.% β-CD significantly improved the tensile and rejection of the HFMs without showing effect on the increase of water flux. The characteristic of the HFMs with different additives combinations proved that the mixture of 5wt.% PVP and 1wt.% β-CD obtained the best membrane performance, with a pure water flux of 427.9 L/ m2·h, a contact angle of 25°, and a rejection to bovine serum albumin (BSA) of 89.7%. The CODcr and UV254 removal rates of dyeing wastewater treatment were 61.10% and 50.41%, respectively. No breakage or leakage points were found after 120d operation showing the reliable mechanical properties. We set the operating flux to 55 L/m2·h and cross flow rate to 10% which can effectively control membrane fouling.


Author(s):  
N. Chin ◽  
S. O. Lai ◽  
K. C. Chong ◽  
S. S. Lee ◽  
C. H. Koo ◽  
...  

The study was concerned with the treatment of tank dewatering produced water using hybrid microfiltration (MF) and ultrafiltration (UF) processes. The pre-treatment MF membrane was fabricated with polyethersulfone (PES), n-methyl-2-pyrrolidone (NMP) and polyvinylpyrrolidone (PVP). The UF membranes meanwhile contained additional component, i.e., titanium dioxide (TiO2) nanoparticles in the range of zero to 1.0 wt.%. The membrane performances were analysed with respect to permeate flux, oil removal and flux recovery ratio. An increase in TiO2 nanoparticles enhanced the pore formation, porosity and pure water permeability due to improved hydrophilicity. The permeate flux of UF membranes increased with the increase of TiO2 nanoparticles and pressure. The oil removal rate by MF process was only 52.35%, whereas the oil rejection efficiency was between 82.34% and 95.71% for UF process. It should be highlighted that the overall oil removal rate could achieve as high as 97.96%. Based on the results, the PES membrane incorporated with 1.0 wt.% TiO2 was proved to be the most promising membrane at a transmembrane pressure of 3 bar. Although 1.0 M NaOH solution could be used as cleaning agent to recover membrane water flux, it is not capable of achieving good results as only 52.18% recovery rate was obtained.


2021 ◽  
Vol 02 (01) ◽  
Author(s):  
Mohd Riduan Jamalludin ◽  
◽  
Siti Khadijah Hubadillah ◽  
Zawati Harun ◽  
Muhamad Zaini Yunos ◽  
...  

This study investigates the effects of rice husk silica (RHS) as additive in the polysulfone membrane to enhance antifouling properties in membrane separation process. The performance (of what?) was evaluated in term of pure water flux (PWF), rejection and antifouling properties. The optimized of normalized flux (Jf /Jo) at different parameter in filtration (pH, ionic strength and tranmembrane-pressure) was carried out by using the response surface methodology (RSM). The results showed that the addition of 4 wt. % RHS give the highest flux at 300.50 L/m².hour (LMH). The highest rejection was found at 3 wt. % of RHS membrane with value 98% for UV254 and 96% for TOC. The optimal value of Jf/Jo was found at 0.62 with the condition of pH: 6.10, ionic strength: 0.05 mol/L and transmembrane-pressure: 2.67 bars. Optimize of RSM analysis from ANOVA also proved that the error of model is less than 0.05% which indicates that the model is significant.


1999 ◽  
Vol 40 (9) ◽  
pp. 113-120 ◽  
Author(s):  
A. Maartens ◽  
P. Swart ◽  
E. P. Jacobs

Organic matter in natural brown water as well as humic acids from a commercial sample were characterised by ultraviolet-visible light-spectroscopy and used in ultrafiltration studies. During ultrafiltration the pure-water flux and the operational flux were measured continuously to determine the degree of membrane fouling. The natural organic matter and commercial humic acid concentrations of the feed and permeate solutions were determined spectrophotometrically. These variables were used in conjunction with conventional flux measurements, to determine the colour-removal efficiency of ultrafiltration as well as the degree of foulant adsorption onto the membranes. Fouled membranes were cleaned with alkaline chemical agents normally used to extract natural organic matter from soil samples. The cleaning efficiency and the effect of cleaning solutions on the membrane selectivity were studied.


2013 ◽  
Vol 750-752 ◽  
pp. 1941-1944
Author(s):  
Jiao Jiao Dong ◽  
Yu Feng Zhang ◽  
Dong Qing Liu

In this article, a series of the PVDF/PPTA blend membranes with porous structure and excellent performance were successfully prepared by the phase transformation method. The effect of the mass ratio of W(PVDF)/W(PPTA) was systematically investigated.The morphology of the blend membranes were examined using scanning electron microscope (SEM). The permeation performance was characterized by measuring pure water flux. Meanwhile, the mechanical properties of membranes were researched. The experiment results confirmed that the blending ratio is a major factor to influence the structure and performance of PVDF/PPTA blend membrane. The blend membranes possess much better permeability than pure PVDF membrane and fairly good the mechanical properties especially for the membrane made by PVDF : PPTA=6 : 1.


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