Fabrication and Performance of Low-Fouling UF Membranes for the Treatment of Isolated Soy Protein Solutions

Consumers are becoming more conscious about the need to include functional and nutritional foods in their diet. This has increased the demand for food extracts rich in proteins and peptides with physiological effects that are used within the food and pharmaceutical industries. Among these protein extracts, soy protein and its derivatives are highlighted. Isolated soy protein (ISP) presents a protein content of at least 90%. Wastewaters generated during the production process contain small proteins (8–50 kDa), and it would be desirable to find a recovery treatment for these compounds. Ultrafiltration membranes (UF) are used for the fractionation and concentration of protein solutions. By the appropriate selection of the membrane pore size, larger soy proteins are retained and concentrated while carbohydrates and minerals are mostly recovered in the permeate. The accumulation and concentration of macromolecules in the proximity of the membrane surface generates one of the most important limitations inherent to the membrane technologies. In this work, three UF membranes based on polyethersulfone (PES) were fabricated. In two of them, polyethylene glycol (PEG) was added in their formulation to be used as a fouling prevention. The membrane fouling was evaluated by the study of flux decline models based on Hermia’s mechanisms.

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ZnO Microfiltration Membranes for Desalination by a Vacuum Flow-Through Evaporation Method

Membranes ◽

10.3390/membranes9120156 ◽

2019 ◽

Vol 9 (12) ◽

pp. 156 ◽

Cited By ~ 1

Author(s):

Shailesh Dangwal ◽

Ruochen Liu ◽

Lyndon D. Bastatas ◽

Elena Echeverria ◽

Chengqian Huang ◽

...

Keyword(s):

Membrane Fouling ◽

Membrane Surface ◽

Water Flux ◽

Atomic Layer ◽

Rejection Rate ◽

Contact Angles ◽

Transfer Resistance ◽

Membrane Pore ◽

Evaporation Method ◽

Flow Through

ZnO was deposited on macroporous α-alumina membranes via atomic layer deposition (ALD) to improve water flux by increasing their hydrophilicity and reducing mass transfer resistance through membrane pore channels. The deposition of ZnO was systemically performed for 4–128 cycles of ALD at 170 °C. Analysis of membrane surface by contact angles (CA) measurements revealed that the hydrophilicity of the ZnO ALD membrane was enhanced with increasing the number of ALD cycles. It was observed that a vacuum-assisted ‘flow-through’ evaporation method had significantly higher efficacy in comparison to conventional desalination methods. By using the vacuum-assisted ‘flow-through’ technique, the water flux of the ZnO ALD membrane (~170 L m−2 h−1) was obtained, which is higher than uncoated pristine membranes (92 L m−2 h−1). It was also found that ZnO ALD membranes substantially improved water flux while keeping excellent salt rejection rate (>99.9%). Ultrasonic membrane cleaning had considerable effect on reducing the membrane fouling.

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Ultrafiltration of wastewater from isolated soy protein production: A comparison of three UF membranes

Journal of Cleaner Production ◽

10.1016/j.jclepro.2009.10.016 ◽

2010 ◽

Vol 18 (3) ◽

pp. 260-265 ◽

Cited By ~ 40

Author(s):

A.S. Cassini ◽

I.C. Tessaro ◽

L.D.F. Marczak ◽

C. Pertile

Keyword(s):

Soy Protein ◽

Protein Production ◽

Isolated Soy Protein ◽

Uf Membranes

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Water Permeates in Ceramic Membrane Modified with Nano Inorganic Coating

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.239-242.27 ◽

2011 ◽

Vol 239-242 ◽

pp. 27-30

Author(s):

Jian Er Zhou ◽

Qi Bing Chang ◽

Ying Chao Dong ◽

Xue Bing Hu ◽

Yong Qing Wang ◽

...

Keyword(s):

Membrane Fouling ◽

Ceramic Membrane ◽

Membrane Surface ◽

Molecular Layer ◽

Pore Wall ◽

Boundary Slip ◽

Membrane Pore ◽

Nano Coating ◽

Inorganic Coating ◽

Modified Membrane

Membrane surface modification is the important method to decrease membrane fouling. The hydrophilic modification of ceramic membrane with nano-sized inorganic coating is prepared by the wet chemical methods. The thin nano coating is not a separating top layer but distributes uniformly on the surface of the membrane pore wall. The coating does not change the structure of the membrane pores. Therefore, water flows on not the pore wall but the nano coating surface. The results show that the water flux of the modified membrane is higher than that of the unmodified membrane despite that the mean pore size of the modified membrane decreases. The “boundary slip” is used to explain this special phenomenon. What generates the slippage? The slippage is relative with the molecular layer adhered tightly on the hydrophilic pore wall, the roughness and the surface charge of the nano coating, the interaction between the ions in water and the nano coating, et al.

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TIO2-ENABLED POLYVYNYLIDENE FLUORIDE FOR PALM OIL MILL EFFLUENT TREATMENT: EFFECTS OF MEMBRANE MORPHOLOGY AND AERATION ON FLUX AND SUSPENDED SOLID REMOVAL

Jurnal Teknologi ◽

10.11113/jurnalteknologi.v84.16961 ◽

2021 ◽

Vol 84 (1) ◽

pp. 107-115

Author(s):

Erna Yuliwaty ◽

Ahmad Fauzi Ismail ◽

Goh Pei Sean ◽

Sri Martini

Keyword(s):

Palm Oil ◽

Membrane Fouling ◽

Polyvinylidene Fluoride ◽

Membrane Surface ◽

Suspended Solid ◽

Effluent Treatment ◽

Palm Oil Mill Effluent ◽

Mixed Matrix Membrane ◽

Membrane Pore ◽

Palm Oil Mill

A polyvinylidene fluoride-based mixed matrix membrane (PVDF- MMM) has been developed to treat palm oil mill effluent (POME). The addition of TiO2 into PVDF membrane was conducted. Hollow fibers were spun from a dope solution containing PVDF/PVP 30K/DMAc/additives by using a dry-jet wet spinning process at different air gaps. AFM image demonstrated that wet spun hollow fiber had a rougher outer surface than that of dry-jet wet spun fibers and exhibited symmetric cross-section structure. Experimental results showed that hydrophilicity of membranes increased with adding of TiO2 particles and the varied air gap length influenced the characteristic of membrane pore size and outer membrane surface roughness. In addition, aeration could increase the turbulence and flux and reduce membrane fouling. The values of flux and suspended solids removal were 92.04 L/m2.hr and 94.86 %, respectively, with the varied aeration flow rate of 2.0, 3.0 and 4.0 mL/min and bubble size distribution of 4.0 µm. Overall, this study has proven that PVDF-based MMM could achieve expected performance for POME treatment.

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Nano-Sized Metal Oxide Modification Applied in Microfiltration Membrane Technology

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.68.145 ◽

2010 ◽

Vol 68 ◽

pp. 145-152 ◽

Cited By ~ 1

Author(s):

Jian Er Zhou ◽

Qi Bing Chang ◽

Yong Qing Wang

Keyword(s):

Metal Oxide ◽

Membrane Fouling ◽

Ceramic Membrane ◽

Membrane Surface ◽

Membrane Technology ◽

Future Research ◽

Membrane Pore ◽

Nano Coating ◽

Inorganic Coating ◽

Modified Membrane

Membrane surface modification is the important method to decrease membrane fouling. Recent efforts have been made to develop the hydrophilic modified ceramic membrane with nano-sized inorganic coating in our research group. In the modified membrane, the nano coating does not form a separating layer, just distributes uniformly on the surface of the membrane pore wall. It results in that: (1) if the feed is water, the water flux of the modified membrane is higher than that of the unmodified one despite the fact that the mean membrane pore size decreases after the modification; (2) if the feed is oily emulsion, the steady flux is obtained in a short time and keeps in the following time. The flux is far higher than that of the unmodified one because the hydrophilic nano coating prevents the cake from forming on the membrane surface. The nano-sized metal oxide modification application in the membrane technology not only expands the newly research area of the membrane technology but also makes the modified ceramic membrane have a good perspective application in the industry. This paper will introduce the development of the modified membrane with nano inorganic coating and give a clear future research direction.

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Analysis of Fouling Characteristics of Diatomite Ceramic Membrane Using Filtration Models

E3S Web of Conferences ◽

10.1051/e3sconf/202123301049 ◽

2021 ◽

Vol 233 ◽

pp. 01049

Author(s):

YANG Yanqing ◽

QIU Yan ◽

LIU Yanhui ◽

ZHAO Yan ◽

LI jing ◽

...

Keyword(s):

Humic Acid ◽

Water Treatment ◽

Membrane Fouling ◽

Municipal Wastewater ◽

Ceramic Membrane ◽

Membrane Surface ◽

Drinking Water Treatment ◽

Polymeric Membrane ◽

Membrane Pore ◽

Fouling Characteristics

Ceramic membrane has made rapid progress in industrial/municipal wastewater treatment and drinking water treatment owing to its advantageous properties over conventional polymeric membrane. The ceramic membrane processes are a rapidly emerging technology for water treatment, yet virtually no information on the performance and fouling mechanisms diatomite ceramic membrane. In this study, filtration experiments were carried out using a mixture of humic acid and kaolin which simulated surface water under constant pressure to reveal fouling characteristics of the filtration of the diatomite ceramic membrane. The results showed that the removal rate of VU254 was 52%~70%, and turbidity was 90%~95% when treat mixed water of 5-10mg/L kaolin and humic acid. And membrane surface retention and membrane pore adsorption were the mainly removal routes. And the flux slowly decreases, rapidly decreases, gradually decreases and stabilizes were three processes of diatomite ceramic membrane fouling. And the first and third stages of membrane fouling mainly caused by complete blocking, and the second stage was mainly controlled by standard blocking. The study found that humic acid would cause both the pore blocking and the fouling of the membrane surface when turbidity was present, especially the membrane surface pollution, it was the major factor of diatomite ceramic membrane fouling.

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Mitigation of Membrane Fouling Using an Electroactive Polyether Sulfone Membrane

Membranes ◽

10.3390/membranes10020021 ◽

2020 ◽

Vol 10 (2) ◽

pp. 21 ◽

Cited By ~ 2

Author(s):

Chunyan Ma ◽

Chao Yi ◽

Fang Li ◽

Chensi Shen ◽

Zhiwei Wang ◽

...

Keyword(s):

Membrane Fouling ◽

Membrane Surface ◽

Water Flux ◽

Underlying Mechanism ◽

Membrane Pore ◽

Emulsified Oil ◽

Toc Removal ◽

Polyether Sulfone ◽

Cake Layer ◽

Pes Membrane

Membrane fouling is the bottleneck limiting the wide application of membrane processes. Herein, we adopted an electroactive polyether sulfone (PES) membrane capable of mitigating fouling by various negatively charged foulants. To evaluate anti-fouling performance and the underlying mechanism of this electroactive PES membrane, three types of model foulants were selected rationally (e.g., bovine serum albumin (BSA) and sodium alginate (SA) as non-migratory foulants, yeast as a proliferative foulant and emulsified oil as a spreadable foulant). Water flux and total organic carbon (TOC) removal efficiency in the filtering process of various foulants were tested under an electric field. Results suggest that under electrochemical assistance, the electroactive PES membrane has an enhanced anti-fouling efficacy. Furthermore, a low electrical field was also effective in mitigating the membrane fouling caused by a mixture of various foulants (containing BSA, SA, yeast and emulsified oil). This result can be attributed to the presence of electrostatic repulsion, which keeps foulants away from the membrane surface. Thereby it hinders the formation of a cake layer and mitigates membrane pore blocking. This work implies that an electrochemical control might provide a promising way to mitigate membrane fouling.

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Effect of organic fouling on micro-pollutant rejection in membrane bioreactor treating municipal solid waste landfill leachate

Water Science & Technology ◽

10.2166/wst.2015.248 ◽

2015 ◽

Vol 72 (4) ◽

pp. 561-571 ◽

Cited By ~ 6

Author(s):

Samunya Sanguanpak ◽

Chart Chiemchaisri ◽

Wilai Chiemchaisri ◽

Kazuo Yamamoto

Keyword(s):

Municipal Solid Waste ◽

Solid Waste ◽

Landfill Leachate ◽

Membrane Fouling ◽

Membrane Bioreactor ◽

Membrane Surface ◽

Membrane Pore ◽

Municipal Solid Waste Landfill ◽

Waste Landfill ◽

Micro Pollutants

Effect of membrane fouling on the removal of micro-pollutants from municipal solid waste landfill leachate, i.e. 4-methyl-2,6-di-tert-butylphenol (BHT), bisphenol A (BPA), and bis(2-ethylhexyl)phthalate (DEHP), in membrane bioreactor (MBR) was investigated. Modifications of membrane surface properties were analyzed to determine their relationship with their removals. Membrane fouling was simulated with foulants of different particle sizes on cellulose acetate (CA) microfiltration membrane to investigate the effect of foulant characteristics on BHT, BPA, and DEHP retention in the filtration experiment. The rejection efficiencies of the organic micro-pollutants in the MBR were 82–97% by fouled membrane, and 70–90% by cleaned membrane. The fouled membrane provided higher rejection of micro-pollutants from about 5% for BPA and BHT to 19% for DEHP. These improvements were due to the modification of membrane surface characteristics in terms of surface morphology, and contact angle after membrane fouling. The degree of rejection was found to be dependent upon the characteristics of foulant deposited on CA membrane surface. Increasing foulant particle size and its density shifted the mechanism of micro-pollutant rejection from membrane pore narrowing to pore blocking and cake formation while increasing pollutant adsorption capacity onto the foulant layer.

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Formation and performance of self-forming dynamic membrane (SFDM) in membrane bioreactor (MBR) for treating low-strength wastewater

Water Science & Technology ◽

10.2166/wst.2018.368 ◽

2018 ◽

Vol 78 (4) ◽

pp. 904-912 ◽

Cited By ~ 4

Author(s):

M. Sabaghian ◽

M. R. Mehrnia ◽

M. Esmaieli ◽

D. Noormohammadi

Keyword(s):

Membrane Fouling ◽

Membrane Bioreactor ◽

Oxygen Demand ◽

Aeration Rate ◽

Synthetic Wastewater ◽

Dynamic Membrane ◽

Filter Surface ◽

Low Shear Stress ◽

And Performance ◽

Uf Membranes

Abstract This study introduces a self-forming dynamic membrane (SFDM) with large-pore mesh filter materials instead of conventional MF/UF membranes for wastewater treatment. Development of SFDM on the mesh filter surface plays a major role in reducing the wastewater turbidity and its performance in a self-formation dynamic membrane bioreactor (SFDMBR). To evaluate formation of the dynamic membrane, biological and hydrodynamic parameters, including mixed liquor suspended solids (MLSS) and aeration rate, were examined. The experimental results showed that with elevation of MLSS in the bioreactor (up to MLSS = 9,000 mg/L), the effluent turbidity diminishes with rapid formation of SFDM, with the shortest formation time (5 min) obtained in SFDM operations, though it results in increased membrane fouling. SFDM was well formed at low aeration rates of 2.5 L/min and 5 L/min, due to very low shear stress on the mesh filter surface, given the results of turbidity in comparison with aeration rates of 10 L/min and 15 L/min. The filtration performance of SFDM in treatment of synthetic wastewater was tested under a constant operational flux (58 L/m2 h). Total chemical oxygen demand (COD) and NH4-N removals were 88–93% and 96–98.8%, respectively. These results indicated that the treatment process can be performed effectively by SFDMBR.

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Coagulation/flocculation/ultrafiltration for natural organic matter removal in drinking water production

Water Science & Technology Water Supply ◽

10.2166/ws.2004.0111 ◽

2004 ◽

Vol 4 (5-6) ◽

pp. 215-222 ◽

Cited By ~ 2

Author(s):

A.R. Costa ◽

M.N. de Pinho

Keyword(s):

Drinking Water ◽

Organic Matter ◽

Natural Organic Matter ◽

Membrane Fouling ◽

Membrane Filtration ◽

Membrane Surface ◽

Water Production ◽

Cellulose Acetate Membranes ◽

Wide Range ◽

Drinking Water Production

Membrane fouling by natural organic matter (NOM), namely by humic substances (HS), is a major problem in water treatment for drinking water production using membrane processes. Membrane fouling is dependent on membrane morphology like pore size and on water characteristics namely NOM nature. This work addresses the evaluation of the efficiency of ultrafiltration (UF) and Coagulation/Flocculation/UF performance in terms of permeation fluxes and HS removal, of the water from Tagus River (Valada). The operation of coagulation with chitosan was evaluated as a pretreatment for minimization of membrane fouling. UF experiments were carried out in flat cells of 13.2×10−4 m2 of membrane surface area and at transmembrane pressures from 1 to 4 bar. Five cellulose acetate membranes were laboratory made to cover a wide range of molecular weight cut-off (MWCO): 2,300, 11,000, 28,000, 60,000 and 75,000 Da. Severe fouling is observed for the membranes with the highest cut-off. In the permeation experiments of raw water, coagulation prior to membrane filtration led to a significant improvement of the permeation performance of the membranes with the highest MWCO due to the particles and colloidal matter removal.

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