Download or read book Macroscopic Graphene Membranes with Tunable Nanopores for Highly Selective Mass Separation written by Doojoon Jang and published by . This book was released on 2018 with total page 139 pages. Available in PDF, EPUB and Kindle. Book excerpt: Membrane-based filtration enables energy-efficient separations of solutes, solvents, or gases, benefiting a wide range of applications including water desalination, nanofiltration, hemodialysis, solvent-based separation, or natural gas purification. Semipermeable polymeric desalination membranes rely on solution-diffusion mechanism to separate water from salts, where selective transport of species arises from their solubility and diffusivity in polymer phase. Despite the remarkable progress in materials, structure, and separation process over the past few decades, today's membranes are subjected to intrinsic challenges ranging from resolving the trade-off between permeability and selectivity to maintaining robust operation with high stability and low fouling. Two dimensional materials have the potential to address some of the above challenges by offering a fundamentally new mechanism to control nanofluidic transport with sustainable nanoscale pores, thereby presenting a platform for next-generation reverse osmosis (RO) or nanofiltration (NF) membranes. Although theoretical investigations of great breadth and depth have been pursued to understand mass transport across the atomically thin materials, experimental efforts are required to engineer and tune nanopore structure in macroscopically large graphene membranes and understand the resulting transport characteristics. Moreover, the effects of interplay between graphene nanopore structure and porous support layer on membrane transport properties need to be considered to identify the structure-function relationship of the nanoporous graphene membranes. This thesis aims at controlling selective graphene nanopore structure for high permeability and selectivity and understanding the tunable membrane transport properties. A two-step process of ion bombardment and oxygen plasma is carried out to introduce a high density of nanopores in large-area graphene membranes. Pore creation parameters are thoroughly explored to investigate the influence on pore size and density. The resulting transport properties of graphene membranes can be tuned to achieve high permeance to water, comparable to that of NF membranes, and highly selective transport of monovalent ions over organic molecules. Nanopore structure introduced in graphene membranes is inspected to quantitatively relate the pore creation parameters with the resulting pore size distributions. A multiscale transport model is constructed to investigate the interplay between nanoporous graphene and support pores that governs osmotic water flux and diffusive solute transport. Internal concentration polarization of draw solutes estimated by the model suggests that achieving narrowly distributed graphene pores with minimal leakage is essential to optimal operation of high-flux asymmetric graphene membranes under forward osmosis. Sterically governed molecular assembly is explored to mitigate residual solute leakage across large, non-selective pores for enhanced membrane selectivity. High molecular weight polymers can electrostatically or covalently assemble across nanoscale defects of graphene to narrow down the effective pore size distribution, sterically and electrostatically hindering transport. Multi-step size-selective polyelectrolyte assembly enables >/=99% retention of divalent ions and organic molecules, promising the potential of graphene in desalination, nanofiltration or organic solvent nanofiltration (OSN). With experimental/theoretical means to characterize membrane structure and transport properties, this thesis forms the basis for regulating nanofluidic mass transport with tunable nanopores and developing atomically thin separation membranes with high selectivity and permeability.

Download or read book Development of Macroscopic Nanoporous Graphene Membranes for Gas Separation written by Michael S. H. Boutilier and published by . This book was released on 2017 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: Separating components of a gas from a mixture is a critical step in several important industrial processes including natural gas purification, hydrogen production, carbon dioxide sequestration, and oxy-combustion. For such applications, gas separation membranes are attractive because they offer relatively low energy costs but can be limited by low flow rates and low selectivities. Nanoporous graphene membranes have the potential to exceed the permeance and selectivity limits of existing gas separation membranes. This is made possible by the atomic thickness of the material, which can support sub-nanometer pores that enable molecular sieving while presenting low resistance to permeate flow. The feasibility of gas separation by graphene nanopores has been demonstrated experimentally on micron-scale areas of graphene. However, scaling up to macroscopic sizes presents significant challenges, including graphene imperfections and control of the selective nanopore size distribution across large areas. The overall objective of this thesis research is to develop macroscopic graphene membranes for gas separation. Investigation reveals that the inherent permeance of large areas of graphene results from the presence of micron-scale tears and nanometer-scale intrinsic defects. Stacking multiple graphene layers is shown to reduce leakage exponentially. A model is developed for the inherent permeance of multi-layer graphene and shown to accurately explain measured flow rates. Applying this model to membranes with created selective pores, it is predicted that by proper choice of the support membrane beneath graphene or adequate leakage sealing, it should be possible to construct a selectively permeable graphene membrane despite the presence of defects. Interfacial polymerization and atomic layer deposition steps during membrane fabrication are shown to effectively seal micron-scale tears and nanometer-scale defects in graphene. The support membrane is designed to isolate intrinsic defects and reduce leakage through tears. Methods of creating a high density of selectively permeable nanopores are explored. Knudsen selectivity is achieved using macroscopic three-layer graphene membranes on polymer supports by high density ion bombardment. Separation ratios exceeding the Knudsen effusion limit are achieved with single-layer graphene on optimized supports by low density ion bombardment followed by oxygen plasma etching, providing evidence of molecular sieving based gas separation through centimeter-scale graphene membranes.

Download or read book Graphene based Membranes for Mass Transport Applications written by Pengzhan Sun and published by Royal Society of Chemistry. This book was released on 2018-09-21 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive overview of graphene-based membrane materials and its applications.

Download or read book Gas Separation Using Nanoporous Single layer Graphene Membranes written by Zhe Yuan (Chemical engineer) and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanoporous single-layer graphene is regarded as a highly promising membrane material for gas separation due to its atomic thickness. When single-layer graphene contains a high density of gas sieving nanoscale pores, it can exhibit both a high gas permeance and a high selectivity, which is beneficial for reducing the cost of gas separation processes. However, significant challenges remain for matching theoretical predictions with experimental measurements and for the real application of graphene membranes for gas separations. To tackle these challenges, in this thesis, I carry out both theoretical and experimental investigations to understand and to improve the gas separation properties of nanoporous single-layer graphene membranes. On the theoretical side, first, using molecular dynamics simulations, I investigate the mechanism of activated gas permeation through sub-nanometer graphene pores when energy barriers exist for pore crossing. I develop an analytical framework based on transition state theory to predict the gas permeance through a given graphene nanopore. Second, I extend the analytical framework mentioned above from sub-nanometer pores to larger pores. I formulate the transport kinetics associated with the direct impingement from the bulk and with the surface diffusion from the adsorption layer on graphene, and then combine them to predict the overall gas permeation rate using a reaction network model. Last, I apply the theory developed above to predict the total gas permeance through a pore ensemble with a realistic pore size distribution, which is generated by Kinetic Monte Carlo simulations. I show that the total gas permeance through a pore ensemble is dominated by a small fraction of large nanopores having low energy barriers of pore crossing. On the experimental side, I demonstrate temperature-dependent gas mixture separation using single-layer graphene membranes. The membranes contain intrinsic nanopores formed during the chemical vapor deposition synthesis of graphene. I investigate the formation mechanism of the intrinsic graphene nanopores, and systematically control the density of the intrinsic graphene nanopores while maintaining appropriate pore sizes for gas sieving. I identify that nanoscale molecular fouling of the graphene surface where graphene pores are partially blocked by hydrocarbon contaminants under experimental conditions, affects both gas permeance and selectivity.

Download or read book Graphene based Membranes for Mass Transport Applications written by Hongwei Zhu and published by Royal Society of Chemistry. This book was released on 2018-09-21 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is great interest in the novel mass-transport properties of graphene-based membrane materials, especially for environmental applications such as wastewater treatment and reuse, gas separation and water desalination. Graphene-based Membranes for Mass Transport Applications is a comprehensive overview of the research in this area. Starting with current state-of-the-art membrane-based filtration and separation technologies, the book then explores the structure, composition and general properties of graphene-based membranes including nanoporous graphene and graphene oxide followed by the selective mass transport properties of the membranes. The final chapters look at their specific use in barrier applications, purification and separation applications and water desalination. Edited by leading researchers, the book provides an introduction and reference to physicists, chemists, material scientists, chemical engineers and students who are entering or already working in the field of graphene-based membrane materials.

Download or read book Mixed Matrix Membranes written by Clara Casado-Coterillo and published by MDPI. This book was released on 2019-12-16 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mixed matrix membranes (MMMs) have attracted a large amount of interest in research laboratories worldwide in recent decades, motivated by the gap between a growing interest in developing novel mixed matrix membranes by various research groups and the lack of large-scale implementation. This Special Issue contains six publications dealing with the current opportunities and challenges of mixed matrix membranes development and applications to solve environmental and health challenges of the society of 21st century.

Download or read book Laser induced Graphene written by Ruquan Ye and published by . This book was released on 2020-11-30 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: LIG is a revolutionary technique that uses a common CO2 infrared laser scriber, like the one used in any machine shop, for the direct conversion of polymers into porous graphene under ambient conditions. This technique combines the preparation and patterning of 3D graphene in a single step, without the use of wet chemicals. The ease in the structural engineering and excellent mechanical properties of the 3D graphene obtained have made LIG a versatile technique for applications across many fields. This book compiles cutting-edge research on LIG by different research groups all over the world. It discusses the strategies that have been developed to synthesize and engineer graphene, including controlling its properties such as porosity, composition, and surface characteristics. The authors are pioneers in the discovery and development of LIG and the book will appeal to anyone involved in nanotechnology, chemistry, environmental sciences, and device development, especially those with an interest in the synthesis and applications of graphene-based materials.

Download or read book Ceramic Membranes for Separation and Reaction written by Kang Li and published by John Wiley & Sons. This book was released on 2007-04-30 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ceramic Membranes for Reaction and Separation is the first single-authored guide to the developing area of ceramic membranes. Starting by documenting established procedures of ceramic membrane preparation and characterization, this title then focuses on gas separation. The final chapter covers ceramic membrane reactors;- as distributors and separators, and general engineering considerations. Chapters include key examples to illustrate membrane synthesis, characterisation and applications in industry. Theoretical principles, advantages and disadvantages of using ceramic membranes under the various conditions are discussed where applicable.

Download or read book Two Dimensional 2D Nanomaterials in Separation Science written by Rasel Das and published by Springer Nature. This book was released on 2021-04-26 with total page 247 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers newly emerging two-dimensional nanomaterials which have been recently used for the purpose of water purification. It focuses on the synthesis methods of 2D materials and answers how scientists/engineers/nanotechnologist/environmentalists could use these materials for fabricating new separation membranes and most probably making commercially feasible technology. The chapters are written by a collection of international experts ensuring a broad view of each topic. The book will be of interest to experienced researchers as well as young scientists looking for an introduction into 2D materials-based cross-disciplinary research.

Download or read book Adsorption and Phase Behaviour in Nanochannels and Nanotubes written by Lawrence J. Dunne and published by Springer Science & Business Media. This book was released on 2009-09-24 with total page 301 pages. Available in PDF, EPUB and Kindle. Book excerpt: Channels of nanotubular dimensions exist in a variety of materials (examples are carbon nanotubes and the nanotubular channels of zeolites and zeotypes) and show promise for numerous applications due to their unique properties. One of their most important properties is their capacity to adsorb molecules and these may exist in a variety of phases. "Adsorption and Phase Behaviour in Nanochannels and Nanotubes" provides an excellent review of recent and current work on adsorption on nanometerials. It is an impressive collection of papers dealing with the adsorption and phase behaviour in nanoporous materials from both experimental and theoretical perspectives. "Adsorption and Phase Behaviour in Nanochannels and Nanotubes" focuses on carbon nanotubes as well as zeolites and related materials.

Download or read book Organic Solvent Nanofiltration written by Andrew Livingston and published by Newnes. This book was released on 2013-11-12 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Separation of molecules present in organic solvents by membrane (nano)filtration has great potential in industries ranging from refining to fine chemical and pharmaceutical synthesis and is currently an area of intensive studies. This will be the first concise reference book offering a critical analysis on this topic. Nanofiltration, is a pressure driven membrane process used to remove solutes with molecular weight in the range of 200-1,000 g mol-1 typically from aqueous streams. A recent innovation is the extension of nanofiltration processes to organic solvents an emerging technology referred to as Organic Solvent Nanofiltration (OSN). Separation of molecules present in organic solvents by nanofiltration has great potential in various processes such as petroleum refining, fine chemical and pharmaceutical synthesis, catalyst recycle, enrichment of aromatics etc. This book summarizes the developments in the field of OSN. It describes materials and methods used for the preparation of organic solvent stable membranes. Various techniques for manufacturing of OSN membranes, their physico-chemical and performance related characterization and membrane transport mechanisms will be discussed and critically evaluated. A summary of the commercially available OSN membranes, their separation properties and manufacturers will also be presented. Finally a detailed overview of the OSN applications in various industrial and laboratory scale processes as well as their future prospective will be presented. Complete coverage of the field of organic Solvent Nanofiltration: theory and industrial applications Provides all you want to know in this fast developing application of membranes in industrial filtration and water purification Applications of membranes - summary of the existing applications and proposed new applications; review and critical analysis of the data on currently available OSN membranes. The benefit of this feature to the users is outlined in the comment of one referee: "I use these types of books as an instant reference, resource and fact checker when I am writing or researching topics in membrane technology. I also read the content carefully to keep myself at the state-of-the-art in the technology. R&D is an expensive and time consuming endeavor so anything learned from the literature is valuable when it helps to guide my efforts". Contains a large number of diagrams /figures (60 approx) which offer graphical explanations of the processes and the mechanisms underlying the processess provides practical and easy to understand examples of practical applications. The user can easily adapt these to his/her specific application Worked examples 15 (approx) Guide the reader through the various parameters, and show the reader the effect of these parameters in the overall design of the process Includes multimedia content, videos and active tables and diagrams Enable the user to add his/her own data and conditions and get results relevant to his/her situation. Tables (25 approx) Provides review and critical analysis of the data on currently available OSN membranes Glossary Summary of the main terms used in OSN

Download or read book Materials Nanoarchitectonics written by Katsuhiko Ariga and published by Elsevier. This book was released on 2023-12-15 with total page 648 pages. Available in PDF, EPUB and Kindle. Book excerpt: Materials Nanoarchitectonics: From Integrated Molecular Systems to Advanced Devices provides the latest information on the design and molecular manipulation of self-organized hierarchically structured systems using tailor-made nanoscale materials as structural and functional units. The book is organized into three main sections that focus on molecular design of building blocks and hybrid materials, formation of nanostructures, and applications and devices. Bringing together emerging materials, synthetic aspects, nanostructure strategies, and applications, the book aims to support further progress, by offering different perspectives and a strong interdisciplinary approach to this rapidly growing area of innovation. This is an extremely valuable resource for researchers, advanced students, and scientists in industry, with an interest in nanoarchitectonics, nanostructures, and nanomaterials, or across the areas of nanotechnology, chemistry, surface science, polymer science, electrical engineering, physics, chemical engineering, and materials science. Offers a nanoarchitectonic perspective on emerging fields, such as metal-organic frameworks, porous polymer materials, or biomimetic nanostructures Discusses different approaches to utilizing "soft chemistry" as a source for hierarchically organized materials Offers an interdisciplinary approach to the design and construction of integrated chemical nano systems Discusses novel approaches towards the creation of complex multiscale architectures

Download or read book Nanotechnology in Membrane Processes written by Kailash Chandra Khulbe and published by Springer Nature. This book was released on 2021-01-09 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanotechnology has been established in membrane technology for decades. In this book, comprehensive coverage is given to nanotechnology applications in synthetic membrane processes, which are used in different fields such as water treatment, separation of gases, the food industry, military use, drug delivery, air filtration, and green chemistry. Nanomaterials such as carbon nanotubes, nanoparticles, and dendrimers are contributing to the development of more efficient and cost-effective water filtration processes. Gas separation and carbon capture can be significantly improved in flue gas applications. Nanoporous membrane systems engineered to mimic natural filtration systems are being actively developed for use in smart implantable drug delivery systems, bio artificial organs, and other novel nano-enabled medical devices. The microscopic structure of nanoporous ceramic membranes, mainly focusing on zeolite materials, as well as the energy-saving effect of membrane separation, contribute to various chemical synthesis processes. In the food industry, nanotechnology has the potential to create new tools for pathogen detection and packaging. For each application, nanotechnology is mostly used to make composite membranes, and the book provides a detailed look at the mechanisms by which the composite membrane works in each application area.

Download or read book Smart Membranes written by Liang-Yin Chu and published by Royal Society of Chemistry. This book was released on 2019-04-03 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt: Smart membranes that respond to environmental stimuli are gaining attention because of their potential use in a variety of applications, from drug delivery to water treatment. Their surface characteristics and/or permeation properties, including pressure-driven hydraulic permeability and concentration-driven diffusional permeability, can be adjusted in response to small chemical and/or physical stimuli in the environment. This book will cover topics such as novel design and fabrication strategies, approaches for controlling structure and performance, as well as cutting-edge applications of smart membranes. It will deliver new insights and fundamentals for both professionals and newcomers in related fields. Edited by an internationally renowned expert and with contributions from key researchers, Smart Membranes provides a comprehensive overview of the topic. It will appeal to students and researchers across materials science, chemistry, chemical engineering, pharmaceutical science and biomedical science.

Download or read book Molecular and Nano Tubes written by Oliver Hayden and published by Springer Science & Business Media. This book was released on 2011-08-04 with total page 477 pages. Available in PDF, EPUB and Kindle. Book excerpt: Molecular- and Nano-Tubes summarizes recent advancements in the synthesis, fabrication and applications of tubular structures. An interdisciplinary overview of innovative science focused on tubular structures is provided. The reader is offered an overview of the different fields that molecular and nano tubes appear in, in order to learn the fundamental basics as well as the applications of these materials. This book also: Shows how nanotechnology creates novel materials by crossing the barriers between biology and material science, electronics and optics, medicine and more Demonstrates that tubes are a fundamental element in nature and used in disparate applications such as ion channels and carbon nanotubes Molecular- and Nano-Tubes is an ideal volume for researchers and engineers working in materials science and nanotechnology.

Download or read book Gas Separation Membranes written by Ahmad Fauzi Ismail and published by Springer. This book was released on 2015-04-28 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the tremendous progress that has been made in the development of gas separation membranes based both on inorganic and polymeric materials. Materials discussed include polymer inclusion membranes (PIMs), metal organic frameworks (MOFs), carbon based materials, zeolites, as well as other materials, and mixed matrix membranes (MMMs) in which the above novel materials are incorporated. This broad survey of gas membranes covers material, theory, modeling, preparation, characterization (for example, by AFM, IR, XRD, ESR, Positron annihilation spectroscopy), tailoring of membranes, membrane module and system design, and applications. The book is concluded with some perspectives about the future direction of the field.

Download or read book Biomimetic and Bioinspired Membranes for New Frontiers in Sustainable Water Treatment Technology written by Amira Abdelrasoul and published by BoD – Books on Demand. This book was released on 2017-12-06 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biomimetic and bioinspired membranes are the most promising type of membrane for multiple usage scenarios, including commercial separation applications as well as water and wastewater treatment technologies. In recent years, aquaporin biomimetic membranes (ABMs) for water purification have raised considerable interest. These membranes display uniquely favorable properties and outstanding performances, such as diverse interactions, varied selective transport mechanisms, superior stability, high resistance to membrane fouling, and distinct adaptability. Biomimetic membranes would make a significant contribution to alleviate water stress, environmental threats, and energy consumption.