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Chan MK, Tan SJ, Yeow ATH, Ng SC, Lau WJ. Zeolite-Based Poly(vinylidene fluoride) Ultrafiltration Membrane: Characterization and Molecular Weight Cut-Off Estimation with Support Vector Regression Modelling. MEMBRANES 2024; 14:91. [PMID: 38668119 PMCID: PMC11052103 DOI: 10.3390/membranes14040091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 03/29/2024] [Accepted: 04/09/2024] [Indexed: 04/28/2024]
Abstract
Zeolite serves as a promising additive for enhancing the hydrophilicity of polymeric membranes, yet its utilization for bolstering the mechanical strength of the membrane remains limited. In this study, poly(vinylidene fluoride) (PVDF) membranes were modified by incorporating various concentrations of zeolite (0.5-2 wt%) to improve not only their mechanical properties, but also other features for water filtration. Membranes with and without zeolite incorporation were fabricated via a dry-wet phase inversion technique, followed by the application of a series of characterization techniques in order to study their morphological structure, mechanical strength, and hydrophilicity. The membrane filtration performance for each membrane was evaluated based on pure water flux and Bovine Serum Albumin (BSA) rejection. Field-Emission Scanning Electron Microscopy (FESEM) images revealed a dense, microvoid-free structure across all of the PVDF membranes, contributing to a high pristine PVDF membrane tensile strength of 14 MPa. The addition of 0.5 wt% zeolite significantly improved the tensile strength up to 19.4 MPa. Additionally, the incorporation of 1 wt% zeolite into PVDF membrane yielded improvements in membrane hydrophilicity (contact angle of 67.84°), pure water flux (63.49% increase), and high BSA rejection (95.76%) compared to pristine PVDF membranes. To further improve the characterization of the zeolite-modified PVDF membranes, the Support Vector Regression (SVR) model was adopted to estimate the molecular weight cut off (MWCO) of the membranes. A coefficient of determination (R2) value of 0.855 was obtained, suggesting that the SVR model predicted the MWCO accurately. The findings of this study showed that the utilization of zeolite is promising in enhancing both the mechanical properties and separation performance of PVDF membranes for application in ultrafiltration processes.
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Affiliation(s)
- Mieow Kee Chan
- Centre for Water Research, Faculty of Engineering and the Built Environment, SEGi University, Petaling Jaya 47810, Malaysia;
| | - Syee Jia Tan
- Centre for Water Research, Faculty of Engineering and the Built Environment, SEGi University, Petaling Jaya 47810, Malaysia;
| | - Andrew T. H. Yeow
- Department of Chemical Engineering, Faculty of Engineering, Universiti Malaya, Kuala Lumpur 50603, Malaysia;
| | - Sok Choo Ng
- Faculty of Arts and Science, International University of Malaya-Wales, Kuala Lumpur 50480, Malaysia;
| | - Woei Jye Lau
- Advanced Membrane Technology Research Centre, Faculty of Chemical and Energy Engineering, Universiti Teknologi Malaysia, Skudai 81310, Malaysia;
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Sharma SK, Das P, Mandal B, Sanfui BK. Fabrication, characterization and optimization of industrial alpha alumina powders based ceramic membrane supports and its applicative potential for CO2/N2 separation. J CO2 UTIL 2022. [DOI: 10.1016/j.jcou.2022.102121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Yuan K, Gu Q, Zhang F, Zhong Z, Xing W. Spatially confined growth of carbon nanotubes in the pore channels of microporous ceramic supports with improved filtration efficiency. NANOSCALE 2022; 14:10091-10100. [PMID: 35792107 DOI: 10.1039/d2nr03121c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Carbon nanotubes (CNTs) with high degrees of uniformity, orientation and controlled dimensions on porous supports are highly desirable for various applications such as separation of O/W emulsions and air purification. In this work, CNTs were fabricated on silicon carbide (SiC) porous supports with different porosities and pore sizes by chemical vapor deposition (CVD). The growth processes of CNTs on the surface and in the pore channels of the SiC support were studied in detail. Based on microstructural characterization by SEM, Raman spectroscopy and TEM, it was found that these CNTs grown in the pore channels of SiC supports had a higher degree of orientation and purity than those grown on the surface due to the spatially confined effect. The growth processes of various types of CNTs on the microporous supports were proposed, which were further verified by CNTs with different steric configurations (S-CNTs and VACNTs) and on Al2O3 porous supports. Moreover, the contribution of CNTs in the pore channels to the filtration efficiency was demonstrated in oil-water emulsion separation and particle removal in air. This work provides significant guidance for the preparation and filtration application of CNTs on porous materials.
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Affiliation(s)
- Kai Yuan
- State Key Laboratory of Materials-Oriented Chemical Engineering, National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China.
| | - Qilin Gu
- State Key Laboratory of Materials-Oriented Chemical Engineering, National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China.
| | - Feng Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China.
| | - Zhaoxiang Zhong
- State Key Laboratory of Materials-Oriented Chemical Engineering, National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China.
| | - Weihong Xing
- State Key Laboratory of Materials-Oriented Chemical Engineering, National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China.
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Jiang Q, Wang Y, Xie Y, Zhou M, Gu Q, Zhong Z, Xing W. Silicon carbide microfiltration membranes for oil-water separation: Pore structure-dependent wettability matters. WATER RESEARCH 2022; 216:118270. [PMID: 35339967 DOI: 10.1016/j.watres.2022.118270] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 03/02/2022] [Accepted: 03/06/2022] [Indexed: 06/14/2023]
Abstract
Both the pore size and surface properties of silicon carbide (SiC) membranes are demonstrated to significantly affect their separation efficiency when used for oily water treatment. However, the potential influences of open porosity together with the pore size of SiC membranes on their surface properties and oil-water separation performance have rarely been investigated. In this work, porous SiC ceramic membranes with tunable open porosity and pore size were purposely prepared and selected to systematically study the effect of pore structure-dependent wettability on the oil-water separation performance. The measured pure water flux of selected membranes as a function of open porosity (34-48%) and pore size (0.43-0.67 μm) was well-fitted by using a modified H-P equation. Interestingly, the hydrophilicity of SiC membranes was improved with the increase in open porosity and pore size, as evidenced by the gradually decreased dynamic water contact angle and underwater adhesion of oil droplets. Further, the open porosity of SiC membranes was found to contribute more to the improved surface wettability. As a result, the stable flux of SiC membranes in oil-in-water (O/W) emulsions was increased by 24% with the increased open porosity while the oil rejection rate remained above 90%. This work quantitatively reveals the contributions of the pore structure to the surface wettability of ceramic membranes, and thus provides an effective pathway to improve their performance in oil-water separation.
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Affiliation(s)
- Qian Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China
| | - Yaxin Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering, National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China
| | - Yuling Xie
- State Key Laboratory of Materials-Oriented Chemical Engineering, National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China
| | - Ming Zhou
- State Key Laboratory of Materials-Oriented Chemical Engineering, National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China
| | - Qilin Gu
- State Key Laboratory of Materials-Oriented Chemical Engineering, National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China.
| | - Zhaoxiang Zhong
- State Key Laboratory of Materials-Oriented Chemical Engineering, National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China
| | - Weihong Xing
- State Key Laboratory of Materials-Oriented Chemical Engineering, National Engineering Research Center for Special Separation Membrane, Nanjing Tech University, Nanjing 210009, China.
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Zhou J, Gu Q, Liu F, Feng S, Zhong Z, Xing W. Low-temperature sintering of silicon carbide membrane supports from disks to single- and 19-channel tubes. Ann Ital Chir 2022. [DOI: 10.1016/j.jeurceramsoc.2022.01.051] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Du J, Ai D, Xiao X, Song J, Li Y, Chen Y, Wang L, Zhu K. Rational Design and Porosity of Porous Alumina Ceramic Membrane for Air Bearing. MEMBRANES 2021; 11:membranes11110872. [PMID: 34832101 PMCID: PMC8622470 DOI: 10.3390/membranes11110872] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 11/05/2021] [Accepted: 11/06/2021] [Indexed: 11/16/2022]
Abstract
Air bearing has been widely applied in ultra-precision machine tools, aerospace and other fields. The restrictor of the porous material is the key component in air bearings, but its performance is limited by the machining accuracy. A combination of optimization design and material modification of the porous alumina ceramic membrane is proposed to improve performance within an air bearing. Porous alumina ceramics were prepared by adding a pore-forming agent and performing solid-phase sintering at 1600 °C for 3 h, using 95-Al2O3 as raw material and polystyrene microspheres with different particle sizes as the pore-forming agent. With 20 wt.% of PS50, the optimum porous alumina ceramic membranes achieved a density of 3.2 g/cm3, a porosity of 11.8% and a bending strength of 150.4 MPa. Then, the sintered samples were processed into restrictors with a diameter of 40 mm and a thickness of 5 mm. After the restrictors were bonded to aluminum shells for the air bearing, both experimental and simulation work was carried out to verify the designed air bearing. Simulation results showed that the load capacity increased from 94 N to 523 N when the porosity increased from 5% to 25% at a fixed gas supply pressure of 0.5 MPa and a fixed gas film thickness of 25 μm. When the gas film thickness and porosity were fixed at 100 μm and 11.8%, respectively, the load capacity increased from 8.6 N to 40.8 N with the gas supply pressure having been increased from 0.1 MPa to 0.5 MPa. Both experimental and simulation results successfully demonstrated the stability and effectiveness of the proposed method. The porosity is an important factor for improving the performance of an air bearing, and it can be optimized to enhance the bearing's stability and load capacity.
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Affiliation(s)
- Jianzhou Du
- School of Materials Science and Engineering, School of Mechanical Engineering, Yancheng Institute of Technology, Yancheng 224051, China; (J.D.); (D.A.); (X.X.); (J.S.); (Y.L.); (Y.C.)
- State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
| | - Duomei Ai
- School of Materials Science and Engineering, School of Mechanical Engineering, Yancheng Institute of Technology, Yancheng 224051, China; (J.D.); (D.A.); (X.X.); (J.S.); (Y.L.); (Y.C.)
| | - Xin Xiao
- School of Materials Science and Engineering, School of Mechanical Engineering, Yancheng Institute of Technology, Yancheng 224051, China; (J.D.); (D.A.); (X.X.); (J.S.); (Y.L.); (Y.C.)
| | - Jiming Song
- School of Materials Science and Engineering, School of Mechanical Engineering, Yancheng Institute of Technology, Yancheng 224051, China; (J.D.); (D.A.); (X.X.); (J.S.); (Y.L.); (Y.C.)
| | - Yunping Li
- School of Materials Science and Engineering, School of Mechanical Engineering, Yancheng Institute of Technology, Yancheng 224051, China; (J.D.); (D.A.); (X.X.); (J.S.); (Y.L.); (Y.C.)
| | - Yuansheng Chen
- School of Materials Science and Engineering, School of Mechanical Engineering, Yancheng Institute of Technology, Yancheng 224051, China; (J.D.); (D.A.); (X.X.); (J.S.); (Y.L.); (Y.C.)
| | - Luming Wang
- School of Materials Science and Engineering, School of Mechanical Engineering, Yancheng Institute of Technology, Yancheng 224051, China; (J.D.); (D.A.); (X.X.); (J.S.); (Y.L.); (Y.C.)
- Correspondence: (L.W.); (K.Z.)
| | - Kongjun Zhu
- State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
- Correspondence: (L.W.); (K.Z.)
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