scholarly journals Surface Modification To Alleviate PVDF Membrane Fouling During Milk Protein Microfiltration

2021 ◽  
Author(s):  
Diba Mirriahi
Keyword(s):  
Contact Angle ◽  
Surface Modification ◽  
Mechanical Strength ◽  
Membrane Fouling ◽  
Polyvinylidene Fluoride ◽  
High Efficiency ◽  
Serum Proteins ◽  
Membrane Surface ◽  
Pvdf Membrane ◽  
Aqueous Treatment

The interest in using polyvinylidene fluoride (PVDF) membrane in order to separate casein and serum proteins has been raised due to its significant stability. However, the high hydrophobicity of PVDF membrane causes severe fouling during filtration processes. Ozonation, a surface modification process in which polar groups would be formed on the membrane surface, is widely known for its high efficiency. In the present study, the main objective was to optimize the ozonation parameters to reach the minimum fouling while the maximum mechanical strength could be retained. The contact angle of a water droplet on the membrane surface decreased from 73.5° to 50.4° after the treatment of the membrane at the optimal gaseous phase ozonation. This indicates an increase in the hydrophilicity of the treated membrane. Also, filtration performance demonstrated a lower fouling occurrence on the treated membrane as compared to the untreated one. Although gaseous ozonation yielded a slightly better performance in comparison to the aqueous treatment, the membrane treated with aqueous phase ozonation was benefited from conserving its mechanical strength. Activated carbon helped decreasing the contact angle and fouling as compared to the non-catalytic aqueous treatment while the tensile strength was not affected

scholarly journals Surface Modification To Alleviate PVDF Membrane Fouling During Milk Protein Microfiltration

2021 ◽  
Author(s):  
Diba Mirriahi
Keyword(s):  
Contact Angle ◽  
Surface Modification ◽  
Mechanical Strength ◽  
Membrane Fouling ◽  
Polyvinylidene Fluoride ◽  
High Efficiency ◽  
Serum Proteins ◽  
Membrane Surface ◽  
Pvdf Membrane ◽  
Aqueous Treatment

The interest in using polyvinylidene fluoride (PVDF) membrane in order to separate casein and serum proteins has been raised due to its significant stability. However, the high hydrophobicity of PVDF membrane causes severe fouling during filtration processes. Ozonation, a surface modification process in which polar groups would be formed on the membrane surface, is widely known for its high efficiency. In the present study, the main objective was to optimize the ozonation parameters to reach the minimum fouling while the maximum mechanical strength could be retained. The contact angle of a water droplet on the membrane surface decreased from 73.5° to 50.4° after the treatment of the membrane at the optimal gaseous phase ozonation. This indicates an increase in the hydrophilicity of the treated membrane. Also, filtration performance demonstrated a lower fouling occurrence on the treated membrane as compared to the untreated one. Although gaseous ozonation yielded a slightly better performance in comparison to the aqueous treatment, the membrane treated with aqueous phase ozonation was benefited from conserving its mechanical strength. Activated carbon helped decreasing the contact angle and fouling as compared to the non-catalytic aqueous treatment while the tensile strength was not affected

scholarly journals The Modification of PVDF Membrane via Crosslinking with Chitosan and Glutaraldehyde as the Crosslinking Agent

2018 ◽  
Vol 18 (1) ◽  
pp. 1
Author(s):  
Romaya Sitha Silitonga ◽  
Nurul Widiastuti ◽  
Juhana Jaafar ◽  
Ahmad Fauzi Ismail ◽  
Muhammad Nidzhom Zainol Abidin ◽  
...  
Keyword(s):  
Contact Angle ◽  
Vinylidene Fluoride ◽  
Membrane Surface ◽  
Pure Water ◽  
Water Flux ◽  
Crosslinking Agent ◽  
Hydrophobic Properties ◽  
Pvdf Membrane ◽  
Pure Water Flux ◽  
Modified Membrane

Poly(vinylidene fluoride) (PVDF) has outstanding properties such as high thermal stability, resistance to acid solvents and good mechanical strength. Due to its properties, PVDF is widely used as a membrane matrix. However, PVDF membrane is hydrophobic properties, so as for specific applications, the surface of membrane needs to be modified to become hydrophilic. This research aims to modify PVDF membrane surface with chitosan and glutaraldehyde as a crosslinker agent. The FTIR spectra showed that the modified membrane has a peak at 1655 cm-1, indicating the imine group (–N=C)- that was formed due to the crosslink between amine group from chitosan and aldehyde group from glutaraldehyde. Results showed that the contact angle of the modified membrane decreases to 77.22° indicated that the membrane hydrophilic properties (< 90°) were enhanced. Prior to the modification, the contact angle of the PVDF membrane was 90.24°, which shows hydrophobic properties (> 90°). The results of porosity, Ɛ (%) for unmodified PVDF membrane was 55.39%, while the modified PVDF membrane has a porosity of 81.99%. Similarly, by modifying the PVDF membrane, pure water flux increased from 0.9867 L/m2h to 1.1253 L/m2h. The enhancement of porosity and pure water flux for the modified PVDF membrane was due to the improved surface hydrophilicity of PVDF membrane.

scholarly journals Design of a Novel Membrane Draft Tube Jet Loop Reactor (MDJLR) and Treatment of Slaughterhouse Wastewater

Membranes ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 155
Author(s):  
Burhanettin Farizoğlu ◽  
Süleyman Uzuner
Keyword(s):  
Membrane Fouling ◽  
High Efficiency ◽  
Draft Tube ◽  
Membrane Surface ◽  
Membrane Bioreactors ◽  
Operating Conditions ◽  
Membrane Module ◽  
Circulation Rate ◽  
Slaughterhouse Wastewater ◽  
Loop Reactor

The most important obstacle to the widespread use of membrane bioreactors (MBRs) is membrane fouling. In this study, a high-efficiency compact MBR was developed. Therefore, the draft tube of the jet loop reactor (JLB) was planned for use as a membrane module. The high-velocity jet streams, which are present according to the nature of the JLBs, provide high crossflow (cut-off force) on the membrane surface. Thus, the produced membrane module is operated in submerged membrane mode. This enhanced JLB modification is named the membrane draft tube jet loop reactor (MDJLR). This new system has a KLa value of 139 h−1 (at E/V of 2.24 kW m−3). In the next stage, treatment of slaughterhouse wastewater with the MDJLR was carried out. Under the 5.5 kg COD m−3 d−1 loading rate, efficiencies over 97% were achieved. The system operated continuously for 50 days without membrane backwashing or cleaning. During this period, fluxes of 3 L m−2·h−1 were approximately obtained at operating conditions of 850 mg L−1 MLSS (mixed liquor suspended solids) concentration, 1 bar suction pressure (∆P), and 3000 L h−1 circulation rate. This developed MDJLR will make jet loop membrane bioreactors (JLMBRs) and MBRs more compact and improve their performance.

scholarly journals Characterization of the Initial Fouling Layer on the Membrane Surface in a Membrane Bioreactor: Effects of Permeation Drag

Membranes ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 121
Author(s):  
Shengli Wang ◽  
Xin Lu ◽  
Lanhe Zhang ◽  
Jingbo Guo ◽  
Haifeng Zhang
Keyword(s):  
Zeta Potential ◽  
Electron Donor ◽  
Energy Barrier ◽  
Polyvinylidene Fluoride ◽  
Membrane Bioreactor ◽  
Membrane Surface ◽  
Permeate Flux ◽  
Pvdf Membrane ◽  
Operating Modes

In this study, the properties of the initial fouling layer on the membrane surface of a bioreactor were investigated under different operating modes (with or without permeate flux) to improve the understanding of the effect of permeation drag on the formation of the initial fouling layer. It was found that protein was the major component in the two types of initial fouling layers, and that the permeation drag enhanced the tryptophan protein-like substances. The attraction of the initial foulants to the polyvinylidene fluoride (PVDF) membrane was ascribed to the high zeta potential and electron donor component (γ−) of the membrane. Thermodynamic analyses showed that the permeation drag-induced fouling layer possessed high hydrophobicity and low γ−. Due to permeation drag, a portion of the foulants overcame an energy barrier before they contacted the membrane surface, which itself possessed a higher fouling propensity. A declining trend of the cohesive strength among the foulants was found with the increasing development of both fouling layers.

Ultrafiltration Behavior of Organic Mixtures Simulating Sweetwater Solutions: Influence of Membrane Surface and Feed Chemistry

2013 ◽  
Vol 65 (4) ◽  
Author(s):  
Indok Nurul Hasyimah Mohd Amin ◽  
Abdul Wahab Mohammad
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Membrane Fouling ◽  
Membrane Surface ◽  
Glycerol Water ◽  
Pvdf Membrane ◽  
Organic Mixtures ◽  
Rich Solution ◽  
Organic Solute ◽  
Pes Membrane

One of the major drawbacks for the successful of ultrafiltration (UF) during pretreatment of glycerin-rich solution is membrane fouling due to the deposition of triglycerides (TG) and fatty acids (FA). In the present study, attempts were made to examine the filtration behaviour of organic mixtures (oleic acid-triglycerides) compared to single organic solute (triglycerides) contained in synthetic glycerol-water solutions (known as sweetwater). Furthermore, the rejections of individual solutes were studied. The TG-FA mixtures permeated preferentially when compared with single TG which is mainly due to the solubility as well as diffusivity of small fatty acid in the TG-FA mixtures. Furthermore, PVDF membrane provided higher fluxes and experienced less fouling than PES membrane for both cases. In case of PVDF membrane, the rejection of fatty acid was 6.20% while oil rejection in glycerol-water plus TG and TG-FA mixtures was 82.42% and 84.67%, respectively. However, PES membrane underwent higher fatty acid rejection (20.93%) as well as oil rejection in single TG (94.70%) and TG-FA mixtures (91.08%). It is noteworthy that the nature of the membrane and the feed characteristics had a significant effect on the fouling potential and filtration performance.

Zein: A Novel Porogen for the Preparation of PVDF Porous Membrane

2014 ◽  
Vol 1078 ◽  
pp. 45-48
Author(s):  
Hui Xia Xuan ◽  
Chun Ju He
Keyword(s):  
Mechanical Strength ◽  
Pore Structure ◽  
Membrane Surface ◽  
Water Flux ◽  
Porous Membrane ◽  
Pvdf Membrane ◽  
Flux Increase

Zein as the hydrophobic porogen was used to prepare the PVDF porous membrane, ATR demonstrate that zein can be washed away conveniently and no existed in membrane bulk. Compared to the reference PVDF membrane, Mechanical strength of modified PVDF membrane is improved and the water flux increase triple due to the large number of micro-sized pore structure on the membrane surface. Zein can be used for the preparation of hydrophobic porous membrane.

scholarly journals Effect of temperature and salt on PVDF membrane wetting properties

2021 ◽  
Author(s):  
Kefan Jiang ◽  
◽  
Hooman Chamani ◽  
Takeshi Matsuura ◽  
Dipak Rana ◽  
...  
Keyword(s):  
Contact Angle ◽  
Polyvinylidene Fluoride ◽  
Membrane Separation ◽  
Feed Solution ◽  
Membrane Distillation ◽  
Effect Of Temperature ◽  
Separation Processes ◽  
Water Contact ◽  
Pvdf Membrane ◽  
Wetting Properties

Membrane distillation (MD) is a thermally driven separation process. Despite many advantages over other membrane separation processes, pore wetting hampers the wide commercial applications of the MD process. In this paper, the effect of temperature and presence (or absence) of salt in the feed solution on the wetting properties of commercial polyvinylidene fluoride (PVDF) membrane during a period of eight weeks was investigated. Liquid entry pressure (LEP) and water contact angle (WCA) were employed to characterize the wetting properties of the PVDF membrane. The result shows that the temperature has a significant impact on the decrease of the contact angle of the PVDF membrane.

scholarly journals Fabrication and Characterization of Nanofibers Membranes using Electrospinning Technology for Oil Removal

2021 ◽  
Vol 18 (4) ◽  
pp. 1338
Author(s):  
Amer Naji Al-Naemi ◽  
Mohammed Amer Abdul-Majeed ◽  
Mustafa H. Al-Furaiji ◽  
Inmar N Ghazi
Keyword(s):  
Polyvinylidene Fluoride ◽  
Membrane Surface ◽  
Water Flux ◽  
Oil Removal ◽  
Nanofiber Membrane ◽  
Pvdf Membrane ◽  
Electrospinning Method ◽  
Average Water ◽  
Graphene Membranes

Oily wastewater is one of the most challenging streams to deal with especially if the oil exists in emulsified form. In this study, electrospinning method was used to prepare nanofiberous polyvinylidene fluoride (PVDF) membranes and study their performance in oil removal. Graphene particles were embedded in the electrospun PVDF membrane to enhance the efficiency of the membranes. The prepared membranes were characterized using a scanning electron microscopy (SEM) to verify the graphene stabilization on the surface of the membrane homogeneously; while FTIR was used to detect the functional groups on the membrane surface. The membrane wettability was assessed by measuring the contact angle. The PVDF and PVDF / Graphene membranes efficiency was tested in separation of emulsified oil from aqueous solutions. The results showed that PVDF-Graphene nanofiber membrane exhibited better performance than the plain PVDF nanofiber membrane with average water flux of 210 and 180 L.m-2.h-1, respectively. Both membranes showed high oil rejection with more than 98%.

scholarly journals A Membrane Modified with Nitrogen-Doped TiO2/Graphene Oxide for Improved Photocatalytic Performance

2019 ◽  
Vol 9 (5) ◽  
pp. 855
Author(s):  
Tingting Li ◽  
Yong Gao ◽  
Junwo Zhou ◽  
Manying Zhang ◽  
Xiaofei Fu ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Polyvinylidene Fluoride ◽  
Membrane Surface ◽  
Pure Water ◽  
Impregnation Method ◽  
Photocatalytic Efficiency ◽  
Pvdf Membrane ◽  
Microfiltration Membrane ◽  
Doped Tio2 ◽  
Nitrogen Doped

An improved photocatalytic microfiltration membrane was successfully prepared by the impregnation method with nitrogen-doped TiO2/graphene oxide (GO) (NTG). By utilizing the unique role of N and GO, the photocatalytic activity of the membrane in UV and sunlight was improved. Compared with the Polyvinylidene Fluoride (PVDF) microfiltration membrane which was modified by TiO2, N-TiO2 (NT) and TiO2-GO (TG), the NTG/PVDF membrane exhibited high photocatalytic efficiency and significantly improved photodegradation power to the methylene blue (MB) solution under ultraviolet light and sunlight, with the photocatalytic efficiency reaching 86.5% and 80.6%, respectively. Scanning electron microscopy (SEM), X-ray diffractometry (XRD) and Fourier transform infrared spectroscopy (FT-IR) were used to analyze the morphology, crystal structure and chemical bonds of the membrane surface. The hydrophilicity of the modified PVDF microfiltration membrane was significantly improved, the flux of the pure water membrane reached 1672 Lm−2h−1, the flux of the MB solution was also significantly improved due to photodegradation. Therefore, the nitrogen-doped titanium dioxide graphene oxide PVDF microfiltration membrane (NTG/PVDF membrane) has great development prospects in sustainable water treatment.

Sign in / Sign up

Export Citation Format

Share Document