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Long L, Guo H, Zhang L, Gan Q, Wu C, Zhou S, Peng LE, Tang CY. Engraving Polyamide Layers by In Situ Self-Etchable CaCO 3 Nanoparticles Enhances Separation Properties and Antifouling Performance of Reverse Osmosis Membranes. Environ Sci Technol 2024; 58:6435-6443. [PMID: 38551393 DOI: 10.1021/acs.est.4c00164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
Nanovoids within a polyamide layer play an important role in the separation performance of thin-film composite (TFC) reverse osmosis (RO) membranes. To form more extensive nanovoids for enhanced performance, one commonly used method is to incorporate sacrificial nanofillers in the polyamide layer during the exothermic interfacial polymerization (IP) reaction, followed by some post-etching processes. However, these post-treatments could harm the membrane integrity, thereby leading to reduced selectivity. In this study, we applied in situ self-etchable sacrificial nanofillers by taking advantage of the strong acid and heat generated in IP. CaCO3 nanoparticles (nCaCO3) were used as the model nanofillers, which can be in situ etched by reacting with H+ to leave void nanostructures behind. This reaction can further degas CO2 nanobubbles assisted by heat in IP to form more nanovoids in the polyamide layer. These nanovoids can facilitate water transport by enlarging the effective surface filtration area of the polyamide and reducing hydraulic resistance to significantly enhance water permeance. The correlations between the nanovoid properties and membrane performance were systematically analyzed. We further demonstrate that the nCaCO3-tailored membrane can improve membrane antifouling propensity and rejections to boron and As(III) compared with the control. This study investigated a novel strategy of applying self-etchable gas precursors to engrave the polyamide layer for enhanced membrane performance, which provides new insights into the design and synthesis of TFC membranes.
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Affiliation(s)
- Li Long
- Membrane-based Environmental & Sustainable Technology Group, Department of Civil Engineering, The University of Hong Kong, Hong Kong SAR 999077, P R China
| | - Hao Guo
- Membrane-based Environmental & Sustainable Technology Group, Department of Civil Engineering, The University of Hong Kong, Hong Kong SAR 999077, P R China
- Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, P R China
| | - Lingyue Zhang
- Membrane-based Environmental & Sustainable Technology Group, Department of Civil Engineering, The University of Hong Kong, Hong Kong SAR 999077, P R China
| | - Qimao Gan
- Membrane-based Environmental & Sustainable Technology Group, Department of Civil Engineering, The University of Hong Kong, Hong Kong SAR 999077, P R China
| | - Chenyue Wu
- Membrane-based Environmental & Sustainable Technology Group, Department of Civil Engineering, The University of Hong Kong, Hong Kong SAR 999077, P R China
| | - Shenghua Zhou
- Membrane-based Environmental & Sustainable Technology Group, Department of Civil Engineering, The University of Hong Kong, Hong Kong SAR 999077, P R China
| | - Lu Elfa Peng
- Membrane-based Environmental & Sustainable Technology Group, Department of Civil Engineering, The University of Hong Kong, Hong Kong SAR 999077, P R China
| | - Chuyang Y Tang
- Membrane-based Environmental & Sustainable Technology Group, Department of Civil Engineering, The University of Hong Kong, Hong Kong SAR 999077, P R China
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Vasco G, Arima V, Boudjelida S, Carraro M, Bianco M, Zizzari A, Perrone E, Galiano F, Figoli A, Cesaria M. Polymeric Membranes Doped with Halloysite Nanotubes Imaged using Proton Microbeam Microscopy. Nanomaterials (Basel) 2023; 13:2970. [PMID: 37999324 PMCID: PMC10674683 DOI: 10.3390/nano13222970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 11/15/2023] [Accepted: 11/16/2023] [Indexed: 11/25/2023]
Abstract
Polymeric membranes are useful tools for water filtration processes, with their performance strongly dependent on the presence of hydrophilic dopants. In this study, polyaniline (PANI)-capped aluminosilicate (halloysite) nanotubes (HNTs) are dispersed into polyether sulfone (PES), with concentrations ranging from 0.5 to 1.5 wt%, to modify the properties of the PES membrane. Both undoped and HNT-doped PES membranes are investigated in terms of wettability (static and time-dependent contact angle), permeance, mechanical resistance, and morphology (using scanning electron microscopy (SEM)). The higher water permeance observed for the PES membranes incorporating PANI-capped HNTs is, finally, assessed and discussed vis-à-vis the real distribution of HNTs. Indeed, the imaging and characterization in terms of composition, spatial arrangement, and counting of HNTs embedded within the polymeric matrix are demonstrated using non-destructive Micro Particle Induced X-ray Emission (µ-PIXE) and Scanning Transmission Ion Microscopy (STIM) techniques. This approach not only exhibits the unique ability to detect/highlight the distribution of HNTs incorporated throughout the whole thickness of polymer membranes and provide volumetric morphological information consistent with SEM imaging, but also overcomes the limits of the most common analytical techniques exploiting electron probes. These aspects are comprehensively discussed in terms of practical analysis advantages.
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Affiliation(s)
- Giovanna Vasco
- CEDAD—Center of Applied Physics, Dating and Diagnostics, Cittadella della Ricerca, University of Salento, SS. 7, Km. 7300, 72100 Brindisi, Italy;
- Department of Mathematics and Physics “Ennio De Giorgi”, University of Salento, Campus Ecotekne, 73100 Lecce, Italy
| | - Valentina Arima
- CNR NANOTEC—Institute of Nanotechnology, c/o Campus Ecotekne, 73100 Lecce, Italy; (M.B.); (A.Z.); (E.P.)
| | - Soufiane Boudjelida
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131 Padova, Italy;
- Department of Material Sciences, University Mohamed El Bachir El Ibrahimi, Bordj Bou Arreridj 34030, Algeria
| | - Mauro Carraro
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131 Padova, Italy;
- Institute on Membrane Technology (CNR-ITM), University of Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Monica Bianco
- CNR NANOTEC—Institute of Nanotechnology, c/o Campus Ecotekne, 73100 Lecce, Italy; (M.B.); (A.Z.); (E.P.)
| | - Alessandra Zizzari
- CNR NANOTEC—Institute of Nanotechnology, c/o Campus Ecotekne, 73100 Lecce, Italy; (M.B.); (A.Z.); (E.P.)
| | - Elisabetta Perrone
- CNR NANOTEC—Institute of Nanotechnology, c/o Campus Ecotekne, 73100 Lecce, Italy; (M.B.); (A.Z.); (E.P.)
| | - Francesco Galiano
- Institute on Membrane Technology (CNR-ITM), Via P. Bucci 17/c, 87036 Rende, CS, Italy; (F.G.); (A.F.)
| | - Alberto Figoli
- Institute on Membrane Technology (CNR-ITM), Via P. Bucci 17/c, 87036 Rende, CS, Italy; (F.G.); (A.F.)
| | - Maura Cesaria
- Department of Mathematics and Physics “Ennio De Giorgi”, University of Salento, Campus Ecotekne, 73100 Lecce, Italy
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Moon SJ, Kim YJ, Kang DR, Lee SY, Kim JH. Fluorine-Containing, Self-Assembled Graft Copolymer for Tuning the Hydrophilicity and Antifouling Properties of PVDF Ultrafiltration Membranes. Polymers (Basel) 2023; 15:3623. [PMID: 37688249 PMCID: PMC10490059 DOI: 10.3390/polym15173623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 08/28/2023] [Accepted: 08/29/2023] [Indexed: 09/10/2023] Open
Abstract
Neat poly(vinylidene fluoride) (PVDF) ultrafiltration (UF) membranes exhibit poor water permeance and surface hydrophobicity, resulting in poor antifouling properties. Herein, we report the synthesis of a fluorine-containing amphiphilic graft copolymer, poly(2,2,2-trifluoroethyl methacrylate)-g-poly(ethylene glycol) behenyl ether methacrylate (PTFEMA-g-PEGBEM), hereafter referred to as PTF, and its effect on the structure, morphology, and properties of PVDF membranes. The PTF graft copolymer formed a self-assembled nanostructure with a size of 7-8 nm, benefiting from its amphiphilic nature and microphase separation ability. During the nonsolvent-induced phase separation (NIPS) process, the hydrophilic PEGBEM chains were preferentially oriented towards the membrane surface, whereas the superhydrophobic PTFEMA chains were confined in the hydrophobic PVDF matrix. The PTF graft copolymer not only increased the pore size and porosity but also significantly improved the surface hydrophilicity, flux recovery ratio (FRR), and antifouling properties of the membrane. The membrane performance was optimal at 5 wt.% PTF loading, with a water permeance of 45 L m-2 h-1 bar-1, a BSA rejection of 98.6%, and an FRR of 83.0%, which were much greater than those of the neat PVDF membrane. Notably, the tensile strength of the membrane reached 6.34 MPa, which indicated much better mechanical properties than those reported in the literature. These results highlight the effectiveness of surface modification via the rational design of polymer additives and the precise adjustment of the components for preparing membranes with high performance and excellent mechanical properties.
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Affiliation(s)
| | | | | | | | - Jong Hak Kim
- Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul 03722, Republic of Korea
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Galata E, Veziri CM, Theodorakopoulos GV, Romanos GE, Pavlatou EA. A Combined Gas and Water Permeances Method for Revealing the Deposition Morphology of GO Grafting on Ceramic Membranes. Membranes (Basel) 2023; 13:627. [PMID: 37504993 PMCID: PMC10385332 DOI: 10.3390/membranes13070627] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 06/22/2023] [Accepted: 06/26/2023] [Indexed: 07/29/2023]
Abstract
The adhesion enhancement of a graphene oxide (GO) layer on porous ceramic substrates is a crucial step towards developing a high-performance membrane for many applications. In this work, we have achieved the chemical anchoring of GO layers on custom-made macroporous disks, fabricated in the lab by pressing α-Al2O3 powder. To this end, three different linkers, polydopamine (PDA), 3-Glycidoxypropyltrimethoxysilane (GPTMS) and (3-Aminopropyl) triethoxysilane (APTMS), were elaborated for their capacity to tightly bind the GO laminate on the ceramic membrane surface. The same procedure was replicated on cylindrical porous commercial ZrO2 substrates because of their potentiality for applications on a large scale. The gas permeance properties of the membranes were studied using helium at 25 °C as a probe molecule and further scrutinized in conjunction with water permeance results. Measurements with helium at 25 °C were chosen to avoid gas adsorption and surface diffusion mechanisms. This approach allowed us to draw conclusions on the deposition morphology of the GO sheets on the ceramic support, the mode of chemical bonding with the linker and the stability of the deposited GO laminate. Specifically, considering that He permeance is mostly affected by the pore structural characteristics, an estimation was initially made of the relative change in the pore size of the developed membranes compared to the bare substrate. This was achieved by interpreting the results via the Knudsen equation, which describes the gas permeance as being analogous to the third power of the pore radius. Subsequently, the calculated relative change in the pore size was inserted into the Hagen-Poiseuille equation to predict the respective water permeance ratio of the GO membranes to the bare substrate. The reason that the experimental water permeance values may deviate from the predicted ones is related to the different surface chemistry, i.e., the hydrophilicity or hydrophobicity that the composite membranes acquire after the chemical modification. Various characterization techniques were applied to study the morphological and physicochemical properties of the materials, like FESEM, XRD, DLS and Contact Angle.
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Affiliation(s)
- Evdokia Galata
- Laboratory of General Chemistry, School of Chemical Engineering, National Technical University of Athens, Zografou Campus, 9, Iroon Polytechniou Str., Zografou, 15780 Athens, Greece
- Institute of Nanoscience and Nanotechnology, N.C.S.R. "Demokritos", Ag. Paraskevi, 15310 Athens, Greece
| | - Charitomeni M Veziri
- Institute of Nanoscience and Nanotechnology, N.C.S.R. "Demokritos", Ag. Paraskevi, 15310 Athens, Greece
| | - George V Theodorakopoulos
- Laboratory of General Chemistry, School of Chemical Engineering, National Technical University of Athens, Zografou Campus, 9, Iroon Polytechniou Str., Zografou, 15780 Athens, Greece
- Institute of Nanoscience and Nanotechnology, N.C.S.R. "Demokritos", Ag. Paraskevi, 15310 Athens, Greece
| | - George Em Romanos
- Institute of Nanoscience and Nanotechnology, N.C.S.R. "Demokritos", Ag. Paraskevi, 15310 Athens, Greece
| | - Evangelia A Pavlatou
- Laboratory of General Chemistry, School of Chemical Engineering, National Technical University of Athens, Zografou Campus, 9, Iroon Polytechniou Str., Zografou, 15780 Athens, Greece
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Schwieters MS, Mathieu-Gaedke M, Westphal M, Dalpke R, Dirksen M, Qi D, Grull M, Bick T, Taßler S, Sauer DF, Bonn M, Wendler P, Hellweg T, Beyer A, Gölzhäuser A, Schwaneberg U, Glebe U, Böker A. Protein Nanopore Membranes Prepared by a Simple Langmuir-Schaefer Approach. Small 2021; 17:e2102975. [PMID: 34643032 DOI: 10.1002/smll.202102975] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 07/26/2021] [Indexed: 06/13/2023]
Abstract
Filtration through membranes with nanopores is typically associated with high transmembrane pressures and high energy consumption. This problem can be addressed by reducing the respective membrane thickness. Here, a simple procedure is described to prepare ultrathin membranes based on protein nanopores, which exhibit excellent water permeance, two orders of magnitude superior to comparable, industrially applied membranes. Furthermore, incorporation of either closed or open protein nanopores allows tailoring the membrane's ion permeability. To form such membranes, the transmembrane protein ferric hydroxamate uptake protein component A (FhuA) or its open-pore variant are assembled at the air-water interface of a Langmuir trough, compressed to a dense film, crosslinked by glutaraldehyde, and transferred to various support materials. This approach allows to prepare monolayer or multilayer membranes with a very high density of protein nanopores. Freestanding membranes covering holes up to 5 μm in diameter are visualized by atomic force microscopy (AFM), helium ion microscopy, and transmission electron microscopy. AFM PeakForce quantitative nanomechanical property mapping (PeakForce QNM) demonstrates remarkable mechanical stability and elastic properties of freestanding monolayer membranes with a thickness of only 5 nm. The new protein membrane can pave the way to energy-efficient nanofiltration.
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Affiliation(s)
- Magnus S Schwieters
- Fraunhofer Institute for Applied Polymer Research IAP, Geiselbergstr. 69, 14476, Potsdam-Golm, Germany
- Polymer Engineering/Polymer Physics, Berlin Institute of Technology (TU Berlin), Ernst-Reuter-Platz 1, 10587, Berlin, Germany
| | - Maria Mathieu-Gaedke
- Fraunhofer Institute for Applied Polymer Research IAP, Geiselbergstr. 69, 14476, Potsdam-Golm, Germany
- Chair of Polymer Materials and Polymer Technologies, Institute of Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| | - Michael Westphal
- Physics of Supramolecular Systems and Surfaces, Faculty of Physics, Bielefeld University, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - Raphael Dalpke
- Physics of Supramolecular Systems and Surfaces, Faculty of Physics, Bielefeld University, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - Maxim Dirksen
- Department of Physical and Biophysical Chemistry, Faculty of Chemistry, Bielefeld University, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - Daizong Qi
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Marco Grull
- Institute of Biotechnology, RWTH Aachen University, Worringer Weg 3, 52074, Aachen, Germany
| | - Thomas Bick
- Department of Biochemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| | - Stephanie Taßler
- Synchrotron SOLEIL, L'Orme des Merisiers, BP48, Gif-Sur-Yvette, Saint-Aubin, 91192, France
| | - Daniel F Sauer
- Institute of Biotechnology, RWTH Aachen University, Worringer Weg 3, 52074, Aachen, Germany
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Petra Wendler
- Department of Biochemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| | - Thomas Hellweg
- Department of Physical and Biophysical Chemistry, Faculty of Chemistry, Bielefeld University, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - André Beyer
- Physics of Supramolecular Systems and Surfaces, Faculty of Physics, Bielefeld University, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - Armin Gölzhäuser
- Physics of Supramolecular Systems and Surfaces, Faculty of Physics, Bielefeld University, Universitätsstr. 25, 33615, Bielefeld, Germany
| | - Ulrich Schwaneberg
- Institute of Biotechnology, RWTH Aachen University, Worringer Weg 3, 52074, Aachen, Germany
- DWI - Leibniz Institute for Interactive Materials e.V., Forckenbeckstr. 50, 52056, Aachen, Germany
| | - Ulrich Glebe
- Fraunhofer Institute for Applied Polymer Research IAP, Geiselbergstr. 69, 14476, Potsdam-Golm, Germany
| | - Alexander Böker
- Fraunhofer Institute for Applied Polymer Research IAP, Geiselbergstr. 69, 14476, Potsdam-Golm, Germany
- Chair of Polymer Materials and Polymer Technologies, Institute of Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
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Diarte C, Lai PH, Huang H, Romero A, Casero T, Gatius F, Graell J, Medina V, East A, Riederer M, Lara I. Insights Into Olive Fruit Surface Functions: A Comparison of Cuticular Composition, Water Permeability, and Surface Topography in Nine Cultivars During Maturation. Front Plant Sci 2019; 10:1484. [PMID: 31798618 PMCID: PMC6878217 DOI: 10.3389/fpls.2019.01484] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 10/25/2019] [Indexed: 05/02/2023]
Abstract
Olive (Olea europaea L.) growing has outstanding economic relevance in Spain, the main olive oil producer and exporter in the world. Fruit skin properties are very relevant for fruit and oil quality, water loss, and susceptibility to mechanical damage, rots, and infestations, but limited research focus has been placed on the cuticle of intact olive fruit. In this work, fruit samples from nine olive cultivars ("Arbequina," "Argudell," "Empeltre," "Farga," "Manzanilla," "Marfil," "Morrut," "Picual," and "Sevillenca") were harvested from an experimental orchard at three different ripening stages (green, turning, and ripe), and cuticular membranes were enzymatically isolated from fruit skin. The total contents of cuticular wax and cutin significantly differed among cultivars both in absolute and in relative terms. The wax to cutin ratio generally decreased along fruit maturation, with the exception of "Marfil" and "Picual." In contrast, increased water permeance values in ripe fruit were observed uniquely for "Argudell," "Morrut," and "Marfil" fruit. The toluidine blue test revealed surface discontinuities on green samples of "Argudell," "Empeltre," "Manzanilla," "Marfil," and "Sevillenca" fruit, but not on "Arbequina," "Farga," "Morrut," or "Picual." No apparent relationship was found between water permeability and total wax coverage or the results of the toluidine blue test. The composition of cuticular waxes and cutin monomers was analyzed in detail, and sections of fruit pericarp were stained in Sudan IV for microscopy observations. Skin surface topography was also studied by means of fringe projection, showing large differences in surface roughness among the cultivars, "Farga" and "Morrut" fruits displaying the most irregular surfaces. Cultivar-related differences in cuticle and surface features of fruit are presented and discussed.
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Affiliation(s)
- Clara Diarte
- Universitat de Lleida, Lleida, Spain
- Postharvest Unit-XaRTA, AGROTÈCNIO, Lleida, Spain
| | - Po-Han Lai
- Massey Agrifood Technology Partnership, Massey University, Palmerston North, New Zealand
| | - Hua Huang
- Julius-von-Sachs Institut für Biowissenschaften, Universität Würzburg, Würzburg, Germany
| | - Agustí Romero
- Oliviculture, Oil Science and Nuts, IRTA-Mas de Bover, Constantí, Spain
| | | | | | - Jordi Graell
- Universitat de Lleida, Lleida, Spain
- Postharvest Unit-XaRTA, AGROTÈCNIO, Lleida, Spain
| | - Vicente Medina
- Universitat de Lleida, Lleida, Spain
- Applied Plant Biotechnology, AGROTÈCNIO, Lleida, Spain
| | - Andrew East
- Massey Agrifood Technology Partnership, Massey University, Palmerston North, New Zealand
| | - Markus Riederer
- Julius-von-Sachs Institut für Biowissenschaften, Universität Würzburg, Würzburg, Germany
| | - Isabel Lara
- Universitat de Lleida, Lleida, Spain
- Postharvest Unit-XaRTA, AGROTÈCNIO, Lleida, Spain
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Idarraga-Mora JA, Lemelin MA, Weinman ST, Husson SM. Effect of Short-Term Contact with C1-C4 Monohydric Alcohols on the Water Permeance of MPD-TMC Thin-Film Composite Reverse Osmosis Membranes. Membranes (Basel) 2019; 9:E92. [PMID: 31357425 DOI: 10.3390/membranes9080092] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 07/15/2019] [Accepted: 07/24/2019] [Indexed: 11/22/2022]
Abstract
In this paper, we discuss the effect of alcohol contact on the transport properties of thin-film composite reverse osmosis membranes. Five commercial membranes were studied to quantify the changes in water permeance and sodium chloride rejection from contact with five C1–C4 monohydric, alcohols. Water permeance generally increased without decreasing rejection after short-term contact. The extent of these changes depends on the membrane and alcohol used. Young′s modulus measurements showed decreased stiffness of the active layer after contacting the membranes with alcohol, suggesting plasticization. Data analysis using a dual-mode sorption model identified positive correlations of the initial water permeance, as well as the change in free energy of mixing between water and the alcohols, with the increase in water permeance after alcohol contact. We suggest that the mixing of water with the alcohols facilitates alcohol penetration into the active layer, likely by disrupting inter-chain hydrogen bonds, thus increasing the free volume for water permeation. Our studies provide a modeling framework to estimate the changes in transport properties after short-term contact with C1–C4 alcohols.
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8
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Zhang R, Liang B, Qu T, Cao B, Li P. High-performance sulfosuccinic acid cross-linked PVA composite pervaporation membrane for desalination. Environ Technol 2019; 40:312-320. [PMID: 28978280 DOI: 10.1080/09593330.2017.1388852] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 09/19/2017] [Indexed: 06/07/2023]
Abstract
Pervaperation (PV), as a novel technology, has shown great promise in fresh water production from salty water. However, the low water flux of the present membranes hinders their practical applications. Here, a new type of PV composite membrane, consisting of a selective skin layer fabricated from poly(vinyl alcohol) (PVA) cross-linked by sulfosuccinic acid and a porous support layer using a commercial polyacrylonitrile (PAN) ultrafiltration membrane, was developed for applications in desalination. The separation performance of S-PVA/PAN composite PV membranes with different S-PVA layer thicknesses was tested in detail. The best result showed a water flux of 27.9 kg m-2 h-1 with a salt rejection of 99.8%, which was obtained at a vacuum of 100 Pa and temperature of 70°C when separating a 35,000 ppm NaCl solution. The S-PVA/PAN composite membranes could also be used for the desalination of high-concentration (100,000 ppm) NaCl solutions with a water flux of 11.2 kg m-2 h-1 with a salt rejection of 99.8%. Moreover, a stable desalination performance was obtained for a 120 h operation time. This study shows the possibility of using PV in desalination applications for seawater, brackish water and reverse osmosis concentrate treatment.
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Affiliation(s)
- Rui Zhang
- a College of Materials Science and Engineering , Beijing University of Chemical Technology , Beijing , People's Republic of China
| | - Bin Liang
- a College of Materials Science and Engineering , Beijing University of Chemical Technology , Beijing , People's Republic of China
| | - Ting Qu
- a College of Materials Science and Engineering , Beijing University of Chemical Technology , Beijing , People's Republic of China
| | - Bing Cao
- a College of Materials Science and Engineering , Beijing University of Chemical Technology , Beijing , People's Republic of China
| | - Pei Li
- a College of Materials Science and Engineering , Beijing University of Chemical Technology , Beijing , People's Republic of China
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9
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Idarraga-Mora JA, Childress AS, Friedel PS, Ladner DA, Rao AM, Husson SM. Role of Nanocomposite Support Stiffness on TFC Membrane Water Permeance. Membranes (Basel) 2018; 8:E111. [PMID: 30453698 PMCID: PMC6315447 DOI: 10.3390/membranes8040111] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 11/13/2018] [Accepted: 11/14/2018] [Indexed: 11/21/2022]
Abstract
This paper discusses the role played by the mechanical stiffness of porous nanocomposite supports on thin-film composite (TFC) membrane water permeance. Helically coiled and multiwall carbon nanotubes (CNTs) were studied as additives in the nanocomposite supports. Mechanical stiffness was evaluated using tensile tests and penetration tests. While a low loading of CNTs caused macrovoids that decreased the structural integrity, adding higher loads of CNTs compensated for this effect, and this resulted in a net increase in structural stiffness. It was found that the Young's modulus of the nanocomposite supports increased by 30% upon addition of CNTs at 2 wt %. Results were similar for both types of CNTs. An empirical model for porous composite materials described the Young's modulus results. The nanocomposite supports were subsequently used to create TFC membranes. TFC membranes with stiffer supports were more effective at preventing declines in water permeance during compression. These findings support the idea that increasing the mechanical stiffness of TFC membrane nanocomposite supports is an effective strategy for enhancing water production in desalination operations.
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Affiliation(s)
- Jaime A Idarraga-Mora
- Department of Chemical and Biomolecular Engineering, Clemson University, 127 Earle Hall, Clemson, SC 29634, USA.
| | - Anthony S Childress
- Department of Physics and Astronomy, and Clemson Nanomaterials Institute, Clemson University, Clemson, SC 29634, USA.
| | - Parker S Friedel
- Department of Chemical and Biomolecular Engineering, Clemson University, 127 Earle Hall, Clemson, SC 29634, USA.
| | - David A Ladner
- Department of Environmental Engineering and Earth Sciences, Clemson University, 342 Computer Court, Anderson, SC 29625, USA.
| | - Apparao M Rao
- Department of Physics and Astronomy, and Clemson Nanomaterials Institute, Clemson University, Clemson, SC 29634, USA.
| | - Scott M Husson
- Department of Chemical and Biomolecular Engineering, Clemson University, 127 Earle Hall, Clemson, SC 29634, USA.
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