Download or read book Mechanisms of Gas Permeation Through Polymer Membranes written by and published by . This book was released on 1991 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of the present study is to investigate the mechanisms of gas transport in and through polymer membranes and the dependence of these mechanisms on pressure and temperature. This information is required for the development of new, energy-efficient membrane processes for the separation of industrial gas mixtures. Such processes are based on the selective permeation of the components of gas mixtures through nonporous polymer membranes. Recent work has been focused on the permeation of gases through membranes made from glassy polymers, i.e., at temperatures below the glass transition of the polymers (Tg). Glassy polymers are very useful membrane materials for gas separations because of their high selectivity toward different gases. Gases permeate through nonporous polymer membranes by a solution-diffusion'' process. Consequently, in order to understand the characteristics of this process it is necessary to investigate also the mechanisms of gas solution and diffusion in glassy polymers. 23 refs., 10 figs., 4 tabs.
Download or read book Mechanisms of Gas Permeation Through Polymer Membranes Summary Technical Report September 1989 August 1991 written by and published by . This book was released on 1991 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of the present study is to investigate the mechanisms of gas transport in and through polymer membranes and the dependence of these mechanisms on pressure and temperature. This information is required for the development of new, energy-efficient membrane processes for the separation of industrial gas mixtures. Such processes are based on the selective permeation of the components of gas mixtures through nonporous polymer membranes. Recent work has been focused on the permeation of gases through membranes made from glassy polymers, i.e., at temperatures below the glass transition of the polymers (Tg). Glassy polymers are very useful membrane materials for gas separations because of their high selectivity toward different gases. Gases permeate through nonporous polymer membranes by a ''solution-diffusion'' process. Consequently, in order to understand the characteristics of this process it is necessary to investigate also the mechanisms of gas solution and diffusion in glassy polymers. 23 refs., 10 figs., 4 tabs.
Download or read book Mechanisms of Gas Permeation Through Polymer Membranes Summary Technical Report September 1991 August 1992 written by and published by . This book was released on 1992 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Progress is reported in two areas: (1) Concentration-temperature superposition principle (CTSP). CTSP is a theoretical model for describing the gas solubility in glassy polymers swollen by the penetrant gas. It has been extended to describe the dependence of gas diffusivity and permeability on penetrant pressure. Further extension to diffusion of gas mixtures is being studied. (2)Solubility of gases in poly(alkyl methacrylates). Solubility of methane in poly(ethyl methacrylate) and poly(n-butyl methacrylate) was measured; the Langmuir capacity constant was found to not reflect a lower excess free volume; an equation is given for relating the constant to the glass transition temperature. Solubility of ethane in the latter polymer is affected by plasticization.
Download or read book Membrane Materials for Gas and Separation written by Yuri Yampolskii and published by John Wiley & Sons. This book was released on 2017-03-20 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: Si containing polymers have been instrumental in the development of membrane gas separation practices since the early 1970s. Their function is to provide a selective barrier for different molecular species, where selection takes place either on the basis of size or on the basis of physical interactions or both. Combines membrane science, organosilicon chemistry, polymer science, materials science, and physical chemistry Only book to consider polymerization chemistry and synthesis of Si-containing polymers (both glassy and rubbery), and their role as membrane materials Membrane operations present environmental benefits such as reduced waste, and recovered/recycled valuable raw materials that are currently lost to fuel or to flares
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 Mechanism of Gas Permeation Through Polymer Membranes Progress Report September 1 1978 May 31 1979 written by and published by . This book was released on 1979 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A new, more exact derivation of the free-volume model of permeation is presented in this report. The free-volume parameters A/sub d/, B/sub d/, and .gamma. have been determined for CO/sub 2/ in polyethylene from diffusivity measurements at 20 and 35/sup 0/C and at pressures of up to 23 atm. The polyethylene was in the form of semicrystalline rods, and the measurements were made with a new type of high-pressure diffusivity apparatus operating under both isobaric and isothermal conditions. The above parameters were used in conjunction with the free-volume model to predict permeability coefficients for the transport of CO/sub 2/ through polyethylene membranes as a function of pressure. The values of the predicted permeability coefficients were found to agree to within 35% or better (on the average) with those obtained directly from permeability measurements with thin polyethylene membranes. The agreement is within the expected limits, considering the assumptions of the free-volume model and the uncertainty in the diffusivity and permeability measurements. A method of determining free-volume parameters directly from permeability measurements was developed for dilute penetrant-polymer systems. This method was used to obtain values of A/sub d/, B/sub d/, and .gamma. for CO/sub 2/, CH/sub 4/, C/sub 2/H/sub 4/, C/sub 2/H/sub 6/, and C/sub 3/H/sub 8/ in polyethylene membranes. The values of B/sub d/ and .gamma. are in about the same range, respectively, as reported for other penetrant-polymer systems. No data appear to have been published previously for A/sub d/. According to the theory, B/sub d/ is thought to be related to the minimum hole size required for the displacement of a penetrant molecule in the polymer, and should depend on both the size and shape of the molecule. This was confirmed by a linear correlation of B/sub d/ with the effective molecular diameters of the above gases; these diameters make allowance for possible orientation of anisometric molecules during diffusion.
Download or read book Materials Science of Membranes for Gas and Vapor Separation written by Benny Freeman and published by John Wiley & Sons. This book was released on 2006-05-12 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: Materials Science of Membranes for Gas and Vapor Separation is a one-stop reference for the latest advances in membrane-based separation and technology. Put together by an international team of contributors and academia, the book focuses on the advances in both theoretical and experimental materials science and engineering, as well as progress in membrane technology. Special attention is given to comparing polymer and inorganic/organic separation and other emerging applications such as sensors. This book aims to give a balanced treatment of the subject area, allowing the reader an excellent overall perspective of new theoretical results that can be applied to advanced materials, as well as the separation of polymers. The contributions will provide a compact source of relevant and timely information and will be of interest to government, industrial and academic polymer chemists, chemical engineers and materials scientists, as well as an ideal introduction to students.
Download or read book Polymeric Gas Separation Membranes written by D.R. Paul and published by CRC Press. This book was released on 2018-05-04 with total page 635 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymeric Gas Separation Membranes is an outstanding reference devoted to discussing the separation of gases by membranes. An international team of contributors examines the latest findings of membrane science and practical applications and explores the complete spectrum of relevant topics from fundamentals of gas sorption and diffusion in polymers to vapor separation from air. They also compare membrane processes with other separation technologies. This essential book will be valuable to all practitioners and students in membrane science and technology.
Download or read book Gas Transport in Glassy Polymers written by Maria Grazia De Angelis and published by MDPI. This book was released on 2021-04-22 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Special Issue of Membranes focuses on several new aspects of fluid transport in glassy polymers, with application in relevant membrane separations such as gas purification, VOC removal and CO2 capture. In particular, the focus lies on novel experimental techniques, and detailed characterization of specific phenomena like polar and multicomponent interactions during transport. The properties of novel materials, such as mixed matrix membranes based on glassy polymers and different selective fillers, are also presented. A critical review of existing modeling approaches to describe the sorption and transport in glassy polymers suitable for membrane separations is provided, including both macroscopic and atomistic models, and relying both on the standard solution–diffusion process and on the facilitated transport mechanism.
Download or read book Gas Permeation Through Chemically Treated Polymer Membranes written by John C. Weigle and published by . This book was released on 1991 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: Investigates the effect of chemically modifying the surface of a polybutadiene membrane on its gas permeability.
Download or read book Fundamental Modeling of Membrane Systems written by Patricia Luis and published by Elsevier. This book was released on 2018-06-29 with total page 371 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fundamental Modelling of Membrane Systems: Membrane and Process Performance summarizes the state-of-the-art modeling approaches for all significant membrane processes, from molecular transport, to process level, helping researchers and students who carry out experimental research save time and accurately interpret experimental data. The book provides an overview of the different membrane technologies, handling micro-, ultra-, and nanofiltration, reverse and forward osmosis, pervaporation, gas permeation, supported liquid membranes, membrane contactors, membrane bioreactors and ion-exchange membrane systems. Examples of hybrid membrane systems are also included. Presents an accessible reference on how to model membranes and membrane processes Provides a clear, mathematical description of mass transfer in membrane systems Written by well-known, prominent authors in the field of membrane science
Download or read book Membrane Gas Separation written by Benny Freeman and published by John Wiley & Sons. This book was released on 2011-06-20 with total page 371 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas separation membranes offer a number of benefits over other separation technologies, and they play an increasingly important role in reducing the environmental impacts and costs of many industrial processes. This book describes recent and emerging results in membrane gas separation, including highlights of nanoscience and technology, novel polymeric and inorganic membrane materials, new membrane approaches to solve environmental problems e.g. greenhouse gases, aspects of membrane engineering, and recent achievements in industrial gas separation. It includes: Hyperbranched polyimides, amorphous glassy polymers and perfluorinated copolymers Nanocomposite (mixed matrix) membranes Polymeric magnetic membranes Sequestration of CO2 to reduce global warming Industrial applications of gas separation Developed from sessions of the most recent International Congress on Membranes and Membrane Processes, Membrane Gas Separation gives a snapshot of the current situation, and presents both fundamental results and applied achievements.
Download or read book Polymer Permeability written by J. Comyn and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 387 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymers are permeable, whilst ceramics, glasses and metals are gener ally impermeable. This may seem a disadvantage in that polymeric containers may allow loss or contamination of their contents and aggressive substances such as water will diffuse into polymeric struc tures such as adhesive joints or fibre-reinforced composites and cause weakening. However, in some cases permeability is an advantage, and one particular area where this is so is in the use of polymers in drug delivery systems. Also, without permeable polymers, we would not enjoy the wide range of dyed fabrics used in clothing and furnishing. The fundamental reason for the permeability of polymers is their relatively high level of molecular motion, a factor which also leads to their high levels of creep in comparison with ceramics, glasses and metals. The aim of this volume is to examine some timely applied aspects of polymer permeability. In the first chapter basic issues in the mathema tics of diffusion are introduced, and this is followed by two chapters where the fundamental aspects of diffusion in polymers are presented. The following chapters, then, each examine some area of applied science where permeability is a key issue. Each chapter is reasonably self-contained and intended to be informative without frequent outside reference. This inevitably leads to some repetition, but it is hoped that this is not excessive.
Download or read book Tests of a free volume Model of Gas Permeation Through Polymer Membranes II written by Shailesh Ranjit Sampat and published by . This book was released on 1984 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polymer Membranes written by T. deV. Naylor and published by iSmithers Rapra Publishing. This book was released on 1996 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes the constitution and application of polymeric membranes in separation processes. The separation processes covered are reverse osmosis and nanofiltration, ultrafiltration, gas separation, pervaporation and ion exchange. An additional indexed section containing several hundred abstracts from the Rapra Polymer Library database provides useful references for further reading.
Download or read book Encyclopedia of Polymeric Nanomaterials written by Shiro Kobayashi and published by Springer. This book was released on 2015-06-12 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last few years, nanoscience and nanotechnology have been the focus of significant research attention, both from academia and industry. This sustained focus has in-turn driven the interdisciplinary field of material science research to the forefront of scientific inquiry through the creation and study of nanomaterials. Nanomaterials play an important role in the development of new materials as they can be used to influence and control physical properties and specific characteristics of other materials. Nanostructured materials that have been created include nanoparticles, nanocapsules, nanoporous materials, polymer multi-layers to name a few. These are increasingly used across applications as diverse as automotive, environment, energy, catalysis, biomedical, pharmaceutical, and polymer industries. The Encyclopedia of Polymeric Nanomaterials (EPN) intends to be a comprehensive reference work on this dynamic field studying nanomaterials within the context of the relationship between molecular structure and the properties of polymeric materials. Alphabetically organized as an encyclopedic Major Reference Work, EPN will cover the subject along multiple classification axes represented by name, source, properties, function, and structures or even processes, applications and usage. The underlying themes of the encyclopedia has been carefully identified to be based not just on material-based and function-based representation but also on structure- and process-based representation. The encyclopedia will have an exclusive focus on polymeric nanomaterials (for e.g., nanoceramics, nanocomposites, quantum dots, thin films) and will be a first of its kind work to have such an organization providing an overview to the concepts, practices and applications in the field. The encyclopedia intends to cover research and development work ranging from the fundamental mechanisms used for the fabrication of polymeric nanomaterials to their advanced application across multiple industries.
Download or read book Polymeric Gas Separation Membranes written by Robert E. Kesting and published by Wiley-Interscience. This book was released on 1993-12-14 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: Supplemented with over 200 helpful illustrations, this book offers an exposition of the chemical natures of hypothetical black box membranes and those of specific polymers. Chemical structure at the functional group level is considered as the synthesis of steric and polar factors.
