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Zhang J, Peng K, Xu ZK, Xiong Y, Liu J, Cai C, Huang X. A comprehensive review on the behavior and evolution of oil droplets during oil/water separation by membranes. Adv Colloid Interface Sci 2023; 319:102971. [PMID: 37562248 DOI: 10.1016/j.cis.2023.102971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 07/01/2023] [Accepted: 07/31/2023] [Indexed: 08/12/2023]
Abstract
Membrane separation technology has significant advantages for treating oil-in-water emulsions. Understanding the evolution of oil droplets could reveal the interfacial and colloidal interactions, facilitate the design of advanced membranes, and improve the separation performances. This review on the characteristic behavior and evolution of oil droplets focuses on the advanced analytical techniques, and the subsequent fouling as well as demulsification effects during membrane separation. A detailed introduction is provided on microscopic observations and numerical simulations of the dynamic evolution of oil droplets, featuring real-time in-situ visualization and accurate reconstruction, respectively. Characteristic behaviors of these oil droplets include attachment, pinning, wetting, spreading, blockage, intrusion, coalescence, and detachment, which have been quantified by specific proposed parameters and criteria. The fouling process can be evaluated using Hermia and resistance models. The related adhesion force and intrusion pressure as well as droplet-droplet/membrane interfacial interactions can be accurately quantified using various force analysis methods and advanced force measurement techniques. It is encouraging to note that oil coalescence has been achieved through various effects such as electrostatic interactions, mechanical actions, Laplace pressure/surface free energy gradients, and synergistic effects on functional membranes. When oil droplets become destabilized and coalesce into larger ones, the functional membranes can overcome the limitations of size-sieving effect to attain higher separation efficiency. This not only bypasses the trade-off between permeability and rejection, but also significantly reduces membrane fouling. Finally, the challenges and potential research directions in membrane separation are proposed. We hope this review will support the engineering of advanced materials for oil/water separation and research on interface science in general.
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Affiliation(s)
- Jialu Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, No.1239 Siping Road, Shanghai 200092, PR China
| | - Kaiming Peng
- State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, No.1239 Siping Road, Shanghai 200092, PR China; Institute of Carbon Neutrality, Tongji University, No.1239 Siping Road, Shanghai 200092, PR China.
| | - Zhi-Kang Xu
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, and Key Lab of Adsorption and Separation Materials & Technologies of Zhejiang Province, Department of Polymer Science and Engineering, Zhejiang University, No.38 Zheda Road, Hangzhou 310027, PR China
| | - Yongjiao Xiong
- State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, No.1239 Siping Road, Shanghai 200092, PR China
| | - Jia Liu
- State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, No.1239 Siping Road, Shanghai 200092, PR China; Institute of Carbon Neutrality, Tongji University, No.1239 Siping Road, Shanghai 200092, PR China
| | - Chen Cai
- State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, No.1239 Siping Road, Shanghai 200092, PR China; Institute of Carbon Neutrality, Tongji University, No.1239 Siping Road, Shanghai 200092, PR China
| | - Xiangfeng Huang
- State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, No.1239 Siping Road, Shanghai 200092, PR China; Institute of Carbon Neutrality, Tongji University, No.1239 Siping Road, Shanghai 200092, PR China.
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2
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Song C, Rutledge GC. Three-Dimensional Imaging of Emulsion Separation through Liquid-Infused Membranes Using Confocal Laser Scanning Microscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:11468-11480. [PMID: 37540768 DOI: 10.1021/acs.langmuir.3c01477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/06/2023]
Abstract
The removal of emulsified oils from water has always been a challenge due to the kinetic stability resulting from the small droplet size and the presence of stabilizing agents. Membrane technology can treat such mixtures, but fouling of the membrane leads to dramatic reductions in the process capacity. Liquid-infused membranes (LIMs) can potentially resolve the issue of fouling. However, their low permeate flux compared with conventional hydrophilic membranes remains a limitation. To gain insight into the mechanism of transport, we use 3D images acquired by confocal laser scanning microscopy (CLSM) to reconstruct the sequence of events occurring during startup and operation of the LIM for removal of dispersed oil from oil-in-water emulsions. We find evidence for coalescence of oil droplets on the surface of and formation of oil channels within the LIM. Using image analysis, we find that the rate at which oil channels are formed within the membrane and the number of channels ultimately govern the permeate flux of oil through the LIMs. Oil concentration in the feed affects the rate of coalescence of oil on the surface of the LIM, which, in turn, affects the channel formation dynamics. The channel formation dynamics also depend on the viscosity of the infused liquid and the operating pressure. A higher affinity to the pore wall for infused liquid than permeating liquid is essential to antifouling behavior. Overall, this work offers insight into the selective permeation of a dispersed liquid phase through a LIM.
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Affiliation(s)
- Chen Song
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Gregory C Rutledge
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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Cui Y, Wang Y, Hao B, Xiao H, Huang X, Shi B. Water-oil dual-channels enabled exceptional anti-fouling performances for separation of emulsified oil pollutant. JOURNAL OF HAZARDOUS MATERIALS 2023; 449:131012. [PMID: 36812725 DOI: 10.1016/j.jhazmat.2023.131012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 02/01/2023] [Accepted: 02/14/2023] [Indexed: 06/18/2023]
Abstract
Oil contamination has been an increasingly concerned environmental issue due to the large quantity of oily wastewater discharged by the industry. The extreme wettability-enabled single-channel separation strategy guarantees efficient separation of oil pollutant from wastewater. However, the ultra-high selective permeability forces the intercepted oil pollutant to form a blocking layer, which weakens the separation capability and slows the kinetics of permeable phase. As a consequence, the single-channel separation strategy fails to maintain a stable flux for a long-term separation process. Herein, we reported a brand-new water-oil dual-channels strategy for accomplishing an ultra-stable long-term separation of emulsified oil pollutant from oil-in-water nano-emulsion by engineering two drastically opposite extreme wettabilities (i.e. superhydrophilicity and superhydrophobicity) to build the water-oil dual-channels. The strategy established the superwetting transport channels to permit water and oil pollutant to permeate through their own channel. In this way, the generation of intercepted oil pollutant was prevented, which guaranteed an exceptional long-lasting (20 h) anti-fouling performance for successful achievement of an ultra-stable separation of oil contamination from oil-in-water nano-emulsion with high flux retention and high separation efficiency. Therefore, our investigations provided a new route for realizing ultra-stable long-term separation of emulsified oil pollutant from wastewater.
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Affiliation(s)
- Yiwen Cui
- National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065, PR China; Department of Biomass Chemistry and Engineering, Sichuan University, Chengdu 610065, PR China
| | - Yujia Wang
- National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065, PR China; Department of Biomass Chemistry and Engineering, Sichuan University, Chengdu 610065, PR China
| | - Baicun Hao
- National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065, PR China
| | - Hanzhong Xiao
- National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065, PR China
| | - Xin Huang
- National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065, PR China; Department of Biomass Chemistry and Engineering, Sichuan University, Chengdu 610065, PR China.
| | - Bi Shi
- National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065, PR China; Department of Biomass Chemistry and Engineering, Sichuan University, Chengdu 610065, PR China
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4
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Gurave PM, Dubey S, Nandan B, Srivastava RK. Pickering Emulsion-Templated Nanocomposite Membranes for Excellent Demulsification and Oil-Water Separation. ACS APPLIED MATERIALS & INTERFACES 2022; 14:54233-54244. [PMID: 36404643 DOI: 10.1021/acsami.2c16483] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
A worldwide steady increase in oily wastewater, due to oil spillage and various industrial discharges, requires immediate efforts toward development of an effective strategy and materials to preserve the natural water bodies. Designing a superwettable fibrous membrane of robust structure and anti-fouling property for efficient separation of oil-water mixtures and emulsions is therefore highly demanding. The electrospun fibrous membrane, which possesses porosity and flexibility and properties including superwettability and tunable functionality, can be considered as apposite materials for this cause. In this approach, we combined two strategies, viz., Pickering emulsion and near gel resin (nGR) emulsion electrospinning together to produce a fibrous nanocomposite membrane for efficient oil-water separation and demulsification. nGR Pickering emulsions were stabilized using hydrophilic SiO2 nanoparticles and successfully optimized for fabricating the crosslinked core sheath-structured fibrous membrane. The prepared membrane provided twofold functionality due to the core sheath structure of the fibers. The crosslinked polystyrene core offered high oil adsorption capacity, whereas SiO2-functionalized crosslinked polyvinyl alcohol sheath provided a rough, superhydrophilic surface with underwater oleophobic behavior to the membrane. The optimized SiO2-Pickering emulsion-templated nanocomposite membrane demonstrated excellent underwater anti-oil adhesion behavior (UWOCA ∼148°) with efficient oil-water separation capacity of more than 99% and separation flux up to 3346 ± 91 L m-2 h-1. The membrane was evaluated against various oil-water emulsions and found to have a superior separation efficiency. Moreover, excellent anti-oil adhesion property provided the intact membrane, where consistent separation performance was achieved up to 10 separation cycles without any loss. The membrane was used for separation of hot oil-water emulsions and showed no structural disintegration or loss in separation performance when exposed to elevated temperatures. The developed nanocomposite membranes could efficiently be used for separation and demulsification, and their applications can be explored in various other fields including selective sorption, catalysis, and storage in future.
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Affiliation(s)
- Pramod M Gurave
- Department of Textile and Fibre Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi110016, India
| | - Shubhang Dubey
- Department of Textile and Fibre Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi110016, India
| | - Bhanu Nandan
- Department of Textile and Fibre Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi110016, India
| | - Rajiv K Srivastava
- Department of Textile and Fibre Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi110016, India
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Elizabeth Butler M, Jonathan Brant A. EMULSION SEPARATION AND FOULING OF ELECTROSPUN POLYACRYLONITRILE MEMBRANES FOR PRODUCED WATER APPLICATIONS. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.122623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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6
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Antibacterial Activity of Silver Nanoflake (SNF)-Blended Polysulfone Ultrafiltration Membrane. Polymers (Basel) 2022; 14:polym14173600. [PMID: 36080676 PMCID: PMC9459915 DOI: 10.3390/polym14173600] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 08/22/2022] [Accepted: 08/27/2022] [Indexed: 02/07/2023] Open
Abstract
The aim of this research was to study the possibility of using silver nanoflakes (SNFs) as an antibacterial agent in polysulfone (PSF) membranes. SNFs at different concentrations (0.1, 0.2, 0.3 and 0.4 wt.%) were added to a PSF membrane dope solution. To investigate the effect of SNFs on membrane performance and properties, the water contact angle, protein separation, average pore size and molecular weight cutoffs were measured, and water flux and antibacterial tests were conducted. The antimicrobial activities of the SNFs were investigated using Escherichia coli taken from river water. The results showed that PSF membranes blended with 0.1 wt.% SNFs have contact angles of 55°, which is less than that of the pristine PSF membrane (81°), exhibiting the highest pure water flux. Molecular weight cutoff values of the blended membranes indicated that the presence of SNFs does not lead to enlargement of the membrane pore size. The rejection of protein (egg albumin) was improved with the addition of 0.1 wt.% SNFs. The SNFs showed antimicrobial activity against Escherichia coli, where the killing rate was dependent on the SNF concentration in the membranes. The identified bacterial colonies that appeared on the membranes decreased with increasing SNF concentration. PSF membranes blended with SNF, to a great degree, possess quality performance across several indicators, showing great potential to be employed as water filtration membranes.
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Usha ZR, Babiker DM, Yu R, Yang J, Che W, Chen X, Li L. Super hydrophilic modified biaxially oriented polypropylene microporous membrane for excellent gravity-driven oil/water emulsion separation. J Memb Sci 2022. [DOI: 10.1016/j.memsci.2022.120840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Wang Y, Yu X, Fan W, Liu R, Liu Y. Alginate-oil gelator composite foam for effective oil spill treatment. Carbohydr Polym 2022; 294:119755. [DOI: 10.1016/j.carbpol.2022.119755] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 06/15/2022] [Accepted: 06/15/2022] [Indexed: 11/02/2022]
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Wang R, Zhu X, Zhu L, Li H, Xue J, Yu S, Liu X, Gan S, Xue Q. Multifunctional superwetting positively charged foams for continuous oil/water emulsion separation and removal of hazardous pollutants from water. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.120683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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10
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Wang F, Liu K, Xi Y, Li Z. One-step electrospinning PCL/ph-LPSQ nanofibrous membrane with excellent self-cleaning and oil-water separation performance. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.124858] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Ma J, Yao M, Yang Y, Zhang X. Comprehensive review on stability and demulsification of unconventional heavy oil-water emulsions. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.118510] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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12
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Song C, Rutledge GC. Electrospun Liquid-Infused Membranes for Emulsified Oil/Water Separation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:2301-2313. [PMID: 35129364 DOI: 10.1021/acs.langmuir.1c03016] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
From an environmental perspective, microfiltration membranes are attractive for the separation of emulsified oils from contaminated water. However, fouling of the membrane is a major drawback of the technology. "Liquid-infused membranes" (LIMs) have the potential to eliminate membrane fouling. Here, we demonstrate the practical application of LIMs for the separation of oil from a stable oil-in-water emulsion and characterize their resistance to fouling. The base membrane is an electrospun nonwoven fibrous layer of the fluorinated copolymer poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP). The surface energy of the PVDF-co-HFP fibers was lowered by the covalent attachment of a fluorinated silane (PFOCTS), and then, the membrane was infused with a perfluoropolyether. The membrane was then challenged with model emulsions of dodecane in water in a cross-flow configuration. This PFOCTS-modified LIM showed better infused liquid stability, permeation selectivity, higher permeate flux than the unmodified LIM, and better anti-fouling properties than the bare membrane without infused liquid. We also examine the mechanism for transport of the dispersed oil phase through the liquid-infused membrane. We find a linear relationship between the dodecane flux and dodecane concentration in the feed and a higher dodecane flux through the PFOCTS-modified membrane than the unmodified one, which suggests that the capture of dodecane droplets from the feed plays an important role in determining the overall rate of permeation. Other factors such as lower viscosity of the infused liquid, larger pore size, and higher operating pressure also improved the permeate flux through the LIMs. Overall, this work provides some guidelines on the design of composite membranes comprising infused liquids and the choice of operating conditions for the filtration process.
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Affiliation(s)
- Chen Song
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Gregory C Rutledge
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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Zhang J, Huang X, Xiong Y, Zheng W, Liu W, He M, Li L, Liu J, Lu L, Peng K. Spider silk bioinspired superhydrophilic nanofibrous membrane for efficient oil/water separation of nanoemulsions. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2021.119824] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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14
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Bhagyaraj S, Sobolčiak P, Al-Ghouti MA, Krupa I. Copolyamide-Clay Nanotube Polymer Composite Nanofiber Membranes: Preparation, Characterization and Its Asymmetric Wettability Driven Oil/Water Emulsion Separation towards Sewage Remediation. Polymers (Basel) 2021; 13:3710. [PMID: 34771267 PMCID: PMC8588559 DOI: 10.3390/polym13213710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 10/15/2021] [Accepted: 10/15/2021] [Indexed: 11/30/2022] Open
Abstract
To address the problem of ever-increasing oily wastewater management, due to its directional liquid transport property, membranes with asymmetric wettability can be effectively used for emulsion separation. This study reports the synthesis of electrospun polymer-clay nanocomposite nanofibers, using co-polyamide polymer (COPA) and halloysite nanotubes (HA) as filler. The influence of clay content on the morphological, thermal and dielectric properties of the polymer composite nanofiber was investigated comprehensively to address the material characteristics of the developed system. The surface structure analysis and contact angle measurements of the electrospun composite nanofibers confirms the change in surface roughness and wettability when the fillers are added to the polymer. The porosity of the composite electrospun nanofiber membrane was found to be 85% with an oil adsorption capacity of 97% and water permeability of 6265 L/m2 h. Furthermore, the asymmetric wettability-driven oil/water emulsion separation abilities of the as-synthesized membranes shows that the separation efficiency of the composite fiber membrane is 10% improved compared to that of the neat fiber membrane, with improved separation time.
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Affiliation(s)
- Sneha Bhagyaraj
- Center for Advanced Materials, Qatar University, Doha P.O. Box 2713, Qatar; (S.B.); (P.S.)
| | - Patrik Sobolčiak
- Center for Advanced Materials, Qatar University, Doha P.O. Box 2713, Qatar; (S.B.); (P.S.)
| | - Mohammad A. Al-Ghouti
- Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University, Doha P.O. Box 2713, Qatar;
| | - Igor Krupa
- Center for Advanced Materials, Qatar University, Doha P.O. Box 2713, Qatar; (S.B.); (P.S.)
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Xu Q, Chen Y, Xiao T, Yang X. A Facile Method to Control Pore Structure of PVDF/SiO 2 Composite Membranes for Efficient Oil/Water Purification. MEMBRANES 2021; 11:membranes11110803. [PMID: 34832032 PMCID: PMC8619804 DOI: 10.3390/membranes11110803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 10/14/2021] [Accepted: 10/16/2021] [Indexed: 11/16/2022]
Abstract
The use of poly(vinylidene fluoride) (PVDF) microfiltration (MF) membranes to purify oily water has received much attention. However, it is challenging to obtain high-performance PVDF microfiltration membranes due to severe surface fouling and rapid decline of permeability. This study explored a new approach to fabricate high-performance PVDF/silica (SiO2) composite membrane via the use of a polymer solution featuring lower critical solution temperature (LCST) characteristics and the non-solvent thermally induced phase separation method (NTIPS). Coupling with morphological observations, the membrane formation kinetics were analyzed in depth to understand the synergistic effect between the LCST solution properties and fabrication conditions in NTIPS. Utilizing such a synergistic effect, the transition from finger-like macrovoid pores to bi-continuous highly connected pores could be flexibly tuned by increasing the PVDF concentration and the weight ratio of SiO2/PVDF in the dope solution and by raising the coagulation temperature to above the LCST of the solution. The filtration experiments with surfactant-stabilized oil-water emulsion showed that the permeation flux of the PVDF/SiO2 composite membranes was higher than 318 L·m-2·h-1·bar-1 and the rejection above 99.2%. It was also shown that the PVDF/SiO2 composite membranes, especially those fabricated above the LCST, demonstrated better hydrophilicity, which resulted in significant enhancement in the anti-fouling properties for oil/water emulsion separation. Compared to the benchmark pure PVDF membrane in oily water purification, the optimal composite membrane T70 was demonstrated via the 3-cycle filtration experiments with a significantly improved flux recovery ratio (Frr) and minimal reduced irreversible fouling (Rir). Overall, with the developed method in this work, facile procedure to tune the membrane morphology and pore structure was demonstrated, resulting in high performance composite membranes suitable for oil/water emulsion separation.
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Affiliation(s)
- Qianqian Xu
- School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, China; (Q.X.); (Y.C.)
| | - Yuchao Chen
- School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, China; (Q.X.); (Y.C.)
| | - Tonghu Xiao
- School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, China; (Q.X.); (Y.C.)
- Correspondence: (T.X.); (X.Y.)
| | - Xing Yang
- Department of Chemical Engineering, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
- Correspondence: (T.X.); (X.Y.)
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