Removal of Natural Organic Matter by Ultrafiltration: Characterisation, Fouling and Cleaning

1999 ◽  
Vol 40 (9) ◽  
pp. 113-120 ◽  
Author(s):  
A. Maartens ◽  
P. Swart ◽  
E. P. Jacobs
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Membrane Fouling ◽  
Pure Water ◽  
Water Flux ◽  
Cleaning Efficiency ◽  
Commercial Sample ◽  
Membrane Selectivity ◽  
Flux Measurements ◽  
Pure Water Flux

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.

scholarly journals Preparation and Characterization of PVDF/g-C3N4/chitosan Nanocomposite Membrane for the Removal of Direct Blue 14 Dye

2021 ◽  
Author(s):  
Parya Hasanzade ◽  
Parvin Gharbani ◽  
Fahime Derakhshan ◽  
Behnaz Memar Maher
Keyword(s):  
Water Content ◽  
Membrane Fouling ◽  
Polyvinylidene Fluoride ◽  
Pure Water ◽  
Water Flux ◽  
Salt Rejection ◽  
Direct Blue ◽  
Pure Water Flux ◽  
Chitosan Membranes

Abstract Polyvinylidene fluoride (PVDF)/g-C3N4/Chitosan thin film membranes were prepared for removal of Direct Blue 14 dye (an anionic dye) from aqueous solutions. PVDF/g-C3N4/Chitosan membranes were prepared by immersing of PVDF/g-C3N4 membrane in solution containing various concentrations of chitosan. The resulting membranes were characterized by XRD, FESEM, TEM and AFM. Also, pure water flux, salt rejection, water content, antifouling properties of prepared membranes were investigated. The resulting demonstrate that pure water flux was decreased by increasing of chitosan concentration, while water content, antifouling properties and salt rejection were increased. It is found that chitosan has major impact on the membrane structural properties due to transform of the PVDF membrane into hydrophilic ones. It is reported that maximum 93% rejection of Direct Blue 14 was obtained by PVDF/g-C3N4/Chitosan membrane. Compared to the PVDF/g-C3N4 membrane, the experimental results showed that PVDF/g-C3N4/Chitosan membranes demonstrated high potential mainly due to greater hydrophilicity and further minimizing membrane fouling.

scholarly journals Parametrization Study of Electrospun Nanofiber Including LiCl Using Response Surface Methodology (RSM) for Water Treatment Application

2020 ◽  
Vol 10 (20) ◽  
pp. 7295
Author(s):  
Jiyeol Bae ◽  
Hyuna Kim ◽  
Saerom Park ◽  
Kwang Soo Kim ◽  
Heechul Choi
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Feed Rate ◽  
Fiber Diameter ◽  
Pure Water ◽  
Interactive Effect ◽  
Water Flux ◽  
Particle Removal ◽  
Flux Measurements ◽  
Pure Water Flux

The influence of the electrospinning parameters on the diameter of the polyethersulfone (PES) nanofibers was demonstrated using response surface methodology. The electrospinning parameters studied were lithium chloride (LiCl) concentration, PES concentration, feed rate, and tip-to-collector distance. The average fiber diameter was correlated to these factors by using a second-order polynomial function at a 95% confidence level. The statistical analysis indicated that LiCl concentration, PES concentration, and feed rate had the significant connection with the fiber diameter, and LiCl concentration was the most important factor in determining the fiber diameter. When LiCl concentration increased, the fiber diameter decreased, because with more LiCl that is added, more applied voltage is needed to overcome the electrostatic attractions. The interactive effect between PES concentration and feed rate, the interactive effect between PES concentration and tip-to-collector distance, and the quadratic coefficients of LiCl concentration were also found to be significant. The adjusted determination coefficient (Radj2) of the model was calculated to be 0.9106. The water flux measurements showed that the decrease in the fiber diameter of the membrane caused the decrease in the initial pure water flux. The retention tests with 0.6 μm polystyrene (PS) suspension indicated that as the fiber diameter decreased, the pore sizes decreased and the particle removal efficiency increased.

Enhanced Permeability and Removal Efficiency for Phenol and Perfluorooctane Sulphonate by a Multifunctional CNT/Al2O3 Membrane with Electrochemical Assistance

2020 ◽  
Vol 20 (9) ◽  
pp. 5951-5958
Author(s):  
Menghan Sun ◽  
Mingrui Cui ◽  
Yibo Wang ◽  
Xinfei Fan ◽  
Chengwen Song
Keyword(s):  
Pore Size ◽  
Removal Efficiency ◽  
Membrane Fouling ◽  
Membrane Separation ◽  
Pure Water ◽  
Water Flux ◽  
Practical Application ◽  
E Coli ◽  
Pure Water Flux ◽  
Electrochemical Assistance

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.

scholarly journals Two-Step Dopamine-to-Polydopamine Modification of Polyethersulfone Ultrafiltration Membrane for Enhancing Anti-Fouling and Ultraviolet Resistant Properties

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2051
Author(s):  
Sri Mulyati ◽  
Syawaliah Muchtar ◽  
Nasrul Arahman ◽  
Yanna Syamsuddin ◽  
Normi Izati Mat Nawi ◽  
...  
Keyword(s):  
Membrane Fouling ◽  
Pure Water ◽  
Water Flux ◽  
Membrane Resistance ◽  
Second Step ◽  
Fouling Resistance ◽  
Pure Water Flux ◽  
Step Mechanism ◽  
Surface Pores ◽  
Hcl Solution

Polydopamine has been widely used as an additive to enhance membrane fouling resistance. This study reports the effects of two-step dopamine-to-polydopamine modification on the permeation, antifouling, and potential anti-UV properties of polyethersulfone (PES)-based ultrafiltration membranes. The modification was performed through a two-step mechanism: adding the dopamine additive followed by immersion into Tris-HCl solution to allow polymerization of dopamine into polydopamine (PDA). The results reveal that the step of treatment, the concentration of dopamine in the first step, and the duration of dipping in the Tris solution in the second step affect the properties of the resulting membranes. Higher dopamine loadings improve the pure water flux (PWF) by more than threefold (15 vs. 50 L/m2·h). The extended dipping period in the Tris alkaline buffer leads to an overgrowth of the PDA layer that partly covers the surface pores which lowers the PWF. The presence of dopamine or polydopamine enhances the hydrophilicity due to the enrichment of hydrophilic catechol moieties which leads to better anti-fouling. Moreover, the polydopamine film also improves the membrane resistance to UV irradiation by minimizing photodegradation’s occurrence.

Fabrication and Properties of Poly(Ether Imide)/Poly(Vinyl Alcohol) Composite Ultrafiltration Membrane

2012 ◽  
Vol 531-532 ◽  
pp. 18-21 ◽  
Author(s):  
Watchanida Chinpa
Keyword(s):  
Composite Membrane ◽  
Membrane Fouling ◽  
Vinyl Alcohol ◽  
Pure Water ◽  
Water Flux ◽  
Composite Membranes ◽  
Dip Coating ◽  
Poly Vinyl Alcohol ◽  
Phase Inversion Technique ◽  
Pure Water Flux

A poly(ether imide) (PEI) composite membrane was prepared by dip coating a PEI membrane pretreated with 2-aminoethanole (AEOH) into an aqueous solution of poly(vinyl alcohol) PVA and glutaraldehyde (GA). PEI membrane support was firstly prepared via phase inversion technique by casting a solution of PEI in N-methylpyrrolidone (NMP), using water as non-solvent. The hydrophilicity, permeability, anti-fouling and mechanical properties of unmodified PEI and PEI/PVA composite membranes were investigated. By comparison with the unmodified PEI membrane, the PEI/PVA composite membrane exhibited a higher pure water flux and an increase in its hydrophilicity. In addition, the flux recovery of the pure water flux of the composite PEI membrane was higher than that of the unmodified PEI membrane. This indicated that the obtained composite membrane could reduce the membrane fouling and improve its use for ultrafiltration.

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

2004 ◽  
Vol 4 (5-6) ◽  
pp. 215-222 ◽  
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.

Preparation and Characterization of Hydrophilic PVDF Hollow Fiber Ultrafiltration Membrane

2011 ◽  
Vol 480-481 ◽  
pp. 201-206
Author(s):  
Li Guo Wang ◽  
Xiu Ju Wang ◽  
Ai Min Wang ◽  
Wen Juan Liu ◽  
Shi Qi Guo ◽  
...  
Keyword(s):  
Acrylic Acid ◽  
Hollow Fiber ◽  
Polyvinylidene Fluoride ◽  
Breaking Strength ◽  
Pure Water ◽  
Water Flux ◽  
Technical Parameters ◽  
Rupture Pressure ◽  
Pure Water Flux

Hydrophilic Polyvinylidene fluoride (PVDF) hollow fiber ultrafiltration membranes were prepared by wet-spinning method. The effects of technical parameters of acrylic acid grafted onto PVDF on the performance of hydrophilic PVDF membranes were investigated via orthogonal test, the technical parameters of preparation of hydrophilic PVDF membranes were determined, and hydrophilic PVDF membranes were prepared. Then hydrophilic PVDF membranes were characterized in terms of breaking strength, breaking elongation, rupture pressure, pure water flux and rejection. The fouling properties and the conditions of acrylic acid grafted onto PVDF were also examined. The results showed that acrylic acid had been grafted onto PVDF, the breaking strength and rupture pressure improved greatly, and the fouling properties were better than PS hollow fiber UF membrane.

THE FEASIBILITY OF KAOLIN AS MAIN MATERIAL FOR LOW COST POROUS CERAMIC HOLLOW FIBRE MEMBRANE PREPARED USING COMBINED PHASE INVERSION AND SINTERING TECHNIQUE

2017 ◽  
Vol 79 (1-2) ◽  
Author(s):  
Siti Khadijah Hubadillah ◽  
Mohd Hafiz Dzarfan Othman ◽  
A. F. Ismail ◽  
Mukhlis A. Rahman ◽  
Juhana Jaafar
Keyword(s):  
Phase Inversion ◽  
Low Cost ◽  
Pure Water ◽  
Porous Ceramic ◽  
Water Flux ◽  
Hollow Fibre ◽  
Hollow Fibre Membrane ◽  
Fibre Membrane ◽  
Pure Water Flux ◽  
And Performance

Ceramic hollow fibre membrane (CHFM) demonstrated superior characteristics and performance in any separation application. The only problem associated with this kind of technology is the high cost. In order to effectively fabricate and produce low cost porous CHFM, a series of CHFMs made of kaolin were fabricated via combined phase inversion and sintering technique. The CHFMs from kaolin named as kaolin hollow fibre membranes (KHFMs) were studied at different kaolin contents of 35 wt.%, 37.5 wt.% and 40 wt.% sintered at 1200ºC. The result indicated that by varying kaolin contents, different morphologies were obtained due to changes in the viscosity of ceramic suspension containing kaolin. The optimum kaolin content for KHFM was identified. It was found that KHFM prepared at 37.5 wt% has a mechanical strength and pure water flux of A and B respectively.  

Influence of Hydrophilic Polymer on Pure Water Permeation, Permeability Coefficient, and Porosity of Polysulfone Blend Membranes

2014 ◽  
Vol 931-932 ◽  
pp. 168-172 ◽  
Author(s):  
Asmadi Ali ◽  
Mohamad Awang ◽  
Ramli Mat ◽  
Anwar Johari ◽  
Mohd Johari Kamaruddin ◽  
...  
Keyword(s):  
Permeability Coefficient ◽  
Pure Water ◽  
Polymer Concentration ◽  
Water Flux ◽  
Hydrophilic Polymer ◽  
Hydrophobic Property ◽  
Water Permeation ◽  
Blend Membranes ◽  
Wet Phase Inversion ◽  
Pure Water Flux

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.

scholarly journals Preparation, characterization and dyeing wastewater treatment of a new PVDF/PMMA five-bore UF membrane with β-cyclodextrin and additive combinations

2021 ◽  
Author(s):  
Xiaozheng Bian ◽  
Jianping Huang ◽  
Lin Qiu ◽  
Chunyan Ma ◽  
Danli Xi
Keyword(s):  
Wastewater Treatment ◽  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Membrane Fouling ◽  
Bovine Serum ◽  
Polyvinylidene Fluoride ◽  
Hollow Fiber Membrane ◽  
Pure Water ◽  
Water Flux ◽  
Dyeing Wastewater

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.

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