Advances in Materials and Processes for Polymeric Membrane Mediated Water Purification 2015

Transcription

1 Advances in Materials and Processes for Polymeric Membrane Mediated Water Purification 2015 Pacific Grove, California, USA February 15-18, 2015 This section includes: List Abstracts

2 Advances in Materials and Processes for Polymeric Membrane Mediated Water Purification POSTERS High-flux Vertically-aligned Carbon Nanotube-Polymer Composite Membrane N. Bui, E. Meshot, S. Kim, S. Guo, K. J. Wu, and F. Fornasiero Lawrence Livermore National Laboratory An Experimental Analysis of Linde Type A Zeolite Water Permeability in a Model Membrane Pinar Cay-Durgun, Andrew Shabilla, Huidan Yin, and Mary Laura Lind Arizona State University Hydrophilic Nylon 6,6 Nanofibers Supported Thin Film Composite Membranes for Forward Osmosis Liwei Huang and Jeffrey R. McCutcheon University of Connecticut Highly Permeable Thin-Film Nanocomposite Membranes for Recovery of Wastewaters by Osmotic Processes Heather L. Jamieson, Sofia C. Herrera, and Mary Laura Lind Arizona State University Dispersion of Hydrophobic and Hydrophilic Inorganic Particles in Polymer Latex Matrix Afsaneh Khosravi, Julia King, Katelyn Kline, Alexander Maltagliati, and Mary L. 5 Lind Arizona State University Effect of Low Temperature Aging Time of Zeolite a Gel on Particle Size in Hydrogel Process Afsaneh Khosravi, Julia A. King, Alexander Maltagliati, Tony Nguyen, Kiah Engebretson, and Mary L. Lind Arizona State University Polyacrylonitrile Supported Thin Film Composite Hollow Fiber Membranes for Forward Osmosis Jian Ren and Jeffrey R. McCutcheon University of Connecticut Membrane structure analysis of hydrated polyamide active layers of commercially available reverse osmosis membranes Sarah B. Smedley and Michael A. Hickner The Pennsylvania State University Anti-fouling Coatings Comprised of Self-assembled Hydrophilic Star Polymers for Water Purification Membranes 9 Ran Wang and Young-Hye Na IBM Almaden Research Center

3 February 15-18, 2015 Asilomar Conference Grounds, Pacific Gove, CA USA 1 High-flux Vertically-aligned Carbon Nanotube-Polymer Composite Membrane N. Bui, E. Meshot, S. Kim, S. Guo, K. J. Wu, F. Fornasiero* Lawrence Livermore National Laboratory 7000 East Avenue, Livermore, CA * fornasiero1@llnl.gov Herein, a composite membrane platform with a-few-nm-wide vertically-aligned carbon nanotubes (VACNTs) as through pores and an impermeable polymer matrix filling the inter-tube spacing is presented. The membrane provides high water permeability and selectivity to model analytes by best leveraging the outstanding mass transport properties of narrow CNT channels. Furthermore, this membrane platform is ideally suited to fundamentally understand the mechanisms of mass transport through CNT pores. VACNTs were catalytically grown via chemical vapor deposition. The as-grown VACNTs arrays were then infiltrated with polymers. Etching was used to open the VACNTs pores for fluid transport. Results show that these membranes sustained ultrahigh liquid and gas transport rates compared with conventional theory predictions, and outstanding moisture vapor transport rates. Moreover, these membranes successfully rejected 100% of neutral 7nm-Au nanoparticles and charged 3-nm dye molecules during dead-end filtration. With appropriate modification, VACNT-polymer composite membranes may provide great opportunities for water purification. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA LLNL-ABS

4 February 15-18, 2015 Asilomar Conference Grounds, Pacific Gove, CA USA 2 An experimental analysis of linde type A zeolite water permeability in a model membrane Pinar Cay-Durgun, Andrew Shabilla, Huidan Yin, Dr. Mary Laura Lind School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ, USA mllind@asu.edu In this poster, we will present our experimental analysis of (Linde type A) LTA permeability in free standing mixed matrix membranes for RO desalination of brackish water using a model system. We synthesized a series of membranes via spin coating on a glass wafer. We applied oxygen plasma etching to remove the barrier polymer layer on the zeolite surface. Then we measured the permeability performance using dead-end filtration. We measured the water flux around pore-closed LTA zeolites embedded in a water-impermeable polymer matrix, and we measured the water flux through pore-open LTA zeolites embedded within a water-impermeable polymer matrix. We analyzed the results with a resistance model. We report characterization of the membranes with atomic force microscopy, scanning electron microscopy, and Fourier transform infrared spectroscopy. Moreover, we used confocal microscopy to determine the actual quantity of zeolites embedded within each model membrane.

5 February 15-18, 2015 Asilomar Conference Grounds, Pacific Gove, CA USA 3 Hydrophilic Nylon 6,6 Nanofibers Supported Thin Film Composite Membranes for Forward Osmosis Liwei Huang and Jeffrey R. McCutcheon* Department of Chemical and Biomolecular Engineering, University of Connecticut, CT 06268, USA *jeff@engr.uconn.edu In this study, a new thin film composite (TFC) forward osmosis (FO) membrane supported by hydrophilic nylon 6,6 nanofibers is demonstrated. Results show that this membrane exhibited 3 fold higher water flux than a commercial HTI-CTA FO membrane. The high flux of this unique membrane is attributed to favorable structural characteristics inherent to the nanofibers, namely a low thickness and tortuosity and a high porosity and hydrophilicity. The structural parameter for our membrane was calculated to be as low as 200 microns. One drawback of nylon 6,6 nanofibers is their propensity to swell in the presence of water. When swollen, these fibers lose their rigidity and thereby impair the membrane performance. We have addressed this issue by modifying an intrinsically hydrophobic nanofiber to have a hydrophilic surface with an interfacially polymerized nylon 6,6 coating. These modified nanofibers exhibited appropriate hydrophilicity yet were resistant to swelling because of their core hydrophobicity.

6 February 15-18, 2015 Asilomar Conference Grounds, Pacific Gove, CA USA 4 Highly Permeable Thin-Film Nanocomposite Membranes for Recovery of Wastewaters by Osmotic Processes Heather L. Jamieson, Sofia C. Herrera, and Dr. Mary Laura Lind 1150 W. University Dr., Apt. 267, Tempe, AZ, (401) , hjamieso@asu.edu Decreasing the film thickness of polymers and incorporation of nanoparticles into the selective thin-film layer of reverse osmosis membranes has resulted in great increases in water permeability by reducing resistance to molecular transport. While interfacial polymerization allows for deposition of thin polymer films with incorporated nanoparticles, the multi-step process makes this synthesis method more difficult and time-consuming than direct solution casting methods. Our work is focused on utilizing simple deposition methods for producing submicron scale nanocomposites of permeable, hydrophilic polymers with zeolitic nanoparticles. We determined the film thickness and water permeation rates of nanocomposites produced by four simple solvent casting methods: spin coating, dilute solution casting, spray deposition and dip coating. We will present our results on the optimal conditions required for production of nanometer-scale film thicknesses and provide the ideal solvent-casting method for production of such water-permeable nanocomposites.

7 February 15-18, 2015 Asilomar Conference Grounds, Pacific Gove, CA USA 5 Dispersion of hydrophobic and hydrophilic inorganic particles in polymer latex matrix Afsaneh Khosravi 1, Julia King, Katelyn Kline 1, Alexander Maltagliati 1, Mary L. Lind* Address, School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ 85287, USA Fax: , address: mllind@asu.edu Although mixed matrix membranes (MMMs) have become incredibly important due to their exceptional properties, accomplishing homogeneous dispersion of the inorganic particles in polymer matrix is still common issue. 1,2 We developed a new, environmentally friendly method to synthesize MMMs and to improve dispersion of inorganic molecular sieve particles within our MMMs. Our investigations show that using water-based polymer latexes decreases the van der Waals attraction between nanoparticles and leads to a great reduction of aggregated particles. To make our MMMs, we used perfluoroalkoxy fluorothermoplastic (PFA) and polyvinylidene chloride (PVDC) as our polymer matrix and hydrophilic and hydrophobic inorganic particles including Zeolite LTA, zeolite ZSM-5, silicalite-1, and ZIF-71. We demonstrated the effectiveness of this method through scanning electron microscopy (SEM), and hydraulically driven water permeation tests. Our results show thorough dispersion of both hydrophilic and hydrophobic particles in latex solutions.

8 Dispersion of (a) zeolite LTA, (b) ZIF-71, and (c) Silicalite particles in PVDC References: 1 Hong, R. Y., Chen, Q. Dispersion of Inorganic Nanoparticles in Polymer Matrices: Challenges and Solutions. Adv Polym Sci. 2015, 267, Oliveira, M., Machado, A. V. Preparation of polymer-based nanocomposites by different routes (IPC Institute for Polymers and Composites/I3N, University of Minho, Guimarães).

9 February 15-18, 2015 Asilomar Conference Grounds, Pacific Gove, CA USA 6 Effect of low temperature aging time of Zeolite A gel on particle size in hydrogel process Afsaneh Khosravi 1, Julia A. King 1, Alexander Maltagliati 1, Tony Nguyen 1, Kiah Engebretson 1, Mary L. Lind 1 * Address, School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ 85287, USA Fax: , address: mllind@asu.edu The extremely hydrophilic nature of Linde Type A (LTA) zeolites make them a suitable candidate for the water-selective nanoparticle in synthesis mixed matrix membranes. LTA zeolites have successfully been incorporated into polyamide reverse osmosis (RO) membranes. 1 In this poster, we systematically monitored the impact of reaction time, reactions temperature, initial aging of the gel solution prior to crystallization on the structure, size of particle, and reaction yield of LTA zeolite synthesis. We used scanning electron microscopy (SEM), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), and X-ray diffraction (XRD). We found that while a decrease in reaction temperature and reaction time reduced particle size, there is a limit for the magnitude of this decrease. However, we found that preliminary heat treatment (aging) of the synthesis-gel at temperatures lower than the crystallization temperature yielded LTA zeolites with smaller particle size, higher relative crystallinity, and fewer impurities. This is because aging at a lower temperature creates more nuclei, leading to an overall decrease in LTA zeolite particle size. The reduction of zeolite particle size by increase ageing of solution is more obvious in the case of higher reaction temperature. 1 Lind, M. L. et al. Influence of Zeolite Crystal Size on Zeolite-Polyamide Thin Film Nanocomposite Membranes. Langmuir. 2009, 25,

10 February 15-18, 2015 Asilomar Conference Grounds, Pacific Gove, CA USA 7 Polyacrylonitrile Supported Thin Film Composite Hollow Fiber Membranes for Forward Osmosis Jian Ren, Jeffrey R. McCutcheon Department of Chemical and Biomolecular Engineering University of Connecticut 191 Auditorium Rd. Unit 3222, Storrs, CT Phone: (860) jeff@engr.uconn.edu Thin film composite (TFC) hollow fiber membranes have shown great promise as a platform for osmotic processes such as forward osmosis (FO) and pressure retarded osmosis (PRO). Previous work on asymmetric FO membranes demonstrated that employing a hydrophilic supporting structure is essential to promote wetting and mitigate concentration polarization. In this study, we have developed an intrinsically hydrophilic polyacrylonitrile (PAN) hollow fiber supported TFC membrane. A selective polyamide thin film was synthesized on the membrane shell side via interfacial polymerization. The impact of fiber pore structure was investigated during our study with some of our membranes exhibiting water flux of 36.6 Lm -2 h -1 using 1 M sodium chloride draw solution against deionized water in PRO mode. These results suggest the potential of utilizing intrinsically hydrophilic polymeric hollow fibers with finely tuned pore structures as a support for TFC membranes for osmotic processes.

11 February 15-18, 2015 Asilomar Conference Grounds, Pacific Gove, CA USA 8 Membrane structure analysis of hydrated polyamide active layers of commercially available reverse osmosis membranes Sarah B. Smedley and Michael A. Hickner Department of Material Science and Engineering The Pennsylvania State University University Park, PA sxb1031@psu.edu The polyamide active layer of commercially available reverse osmosis membranes was studied at various relative humilities to better understand how the structure of the active layer changes when hydrated. The active layers were hydrated with dilute HOD in H 2 O (5% mol D 2 O in H 2 O) while simultaneously collecting FTIR spectra. The OD stretch peak was monitored to measure how water was interacting with the active layer. A peak fitting routine was employed to distinguish between populations of water hydrogen bonding with the active layer functional groups. The fingerprint region was used to analyze changes in the vibrational signature of specific functional groups and to understand how different chemical moieties interact with water. This work shows how altering the chemistry of the active layer will affect the functional groups interactions with water and therefore impact the transport properties of the materials.

12 February 15-18, 2015 Asilomar Conference Grounds, Pacific Gove, CA USA 9 Anti-fouling Coatings Comprised of Self-assembled Hydrophilic Star Polymers for Water Purification Membranes. Ran Wang, Young-Hye Na IBM Almaden Research Center, 650 Harry Road, San Jose, CA Phone: (631) , wangra@us.ibm.com We reported a novel anti-fouling coatings comprising self-assembled nanogel star polymers with hydrophobic polystyrene (PS) core and hydrophilic arms. The hydrophilic arms are composed of neutral hydrophilic moieties (ex. polyethylene glycol) and/or charged hydrophilic species (ex. ammonium or carboxylic acid). The functionalized nanogel star polymers can be assembled on the surface of hydrophobic UF or MF membranes in an aqueous environment through the hydrophobic interaction between the membrane surfaces with the hydrophobic PS cores, forming single-layered polymer coatings with high chemical and physical stability. The water purification membranes (MF, UF) modified with the ultra-thin star polymer coatings showed enhanced antifouling behaviors toward organic or emulsified oil foulants, resulting higher water flux in crossflow filtration processes. Moreover, the star polymer coatings exhibited good chemical and physical stability without losing their anti-fouling efficiency.