Author: Lixin Chu
Publisher:
ISBN:
Category :
Languages : en
Pages : 238

Get Book Here

Book Description

Author: Renate Marina de Vos
Publisher:
ISBN: 9789036511414
Category :
Languages : en
Pages : 134

Get Book Here

Book Description

Author: N.K. Kanellopoulos
Publisher: Elsevier
ISBN: 0080540325
Category : Technology & Engineering
Languages : en
Pages : 525

Get Book Here

Book Description
This book is dedicated to the rapidly growing field of microporous ceramic membranes with separating layers of pore diameter less than 2nm. The chapters of this book bring forward a wide range of issues, namely fundamentals of complex sorption and transport processes in micropore structures, highly innovative methods of preparation of microporous membranes and examples of their possible commercial applications. This book presents insights by distinguished investigators, who have contributed significantly to the advance of research efforts in the diverse topics described herein. Recently, significant progress has been made with respect to the development of novel microporous asymmetric membranes, mainly involving modification by means of deposition of additional material within the pores of the substrates. Most state-of-the-art technologies aiming in the development of microporous ceramic membrane are presented in the third section of the book. These include several material deposition methods and techniques on macroporous or mesoporous supports and substrates from the liquid or vapour phase, namely those involving sol-gel, zeolite and chemical vapour deposition techniques. In addition to the above-mentioned methods, the classical technique of carbonizing polymeric deposits along with one of the novel techniques of plasma-treating, organically deposited Langmuir-Blodgett films, are also presented. Nanophase mixed ionic-electron membranes for enhanced oxygen transport are described, which pose a strong candidacy for a number of significant commercial applications.

Author: Shaaima Al-Akwaa
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
Zeolite membranes have great potential in gas separation applications because of their unique selective properties. The main challenge is in synthesizing defect-free zeolite membranes. In this study, we synthesized silicalite-1 zeolite membranes on ceramic supports composed of Al2O3 and TiO2 using the pore-plugging method. We investigated the effect of the fill-level in the autoclave during the synthesis on the membrane performance. In particular, we were interested in determining the conditions at which the defects' contribution to the total transport is minimized. We adopted and further developed the approach proposed by Carter (2019) to quantify the permeance contribution through defects. Comparing the membrane performance before and after calcination, we proposed several modifications to the original analysis of Carter (2019). Knowing the defect transport contribution, we determined the corrected diffusivity, an intrinsic property of zeolite crystals at a given temperature, of several adsorbed gases on silicalite-1 crystals. The defect's contribution decreased as the autoclave fill-level increased from 94 to 98%. A further increase in the autoclave fill-level introduced more defects and caused the autoclave lid to rupture. Despite the differences in the membranes' performance arising from the autoclave fill-level, the corrected diffusivities of CO2, CH4, and N2 in silicalite-1 showed minimal variation from membrane to membrane. This proves the validity of the proposed characterization method. Moreover, the reported corrected diffusivities are comparable to the literature's values, found using other characterization methods. However, none of the previously used methods is as simple and straightforward as the one we further developed in this study.

Author: Ali Abdali
Publisher:
ISBN: 9783954047048
Category :
Languages : en
Pages : 122

Get Book Here

Book Description

Author: Reyes Mallada
Publisher: Elsevier
ISBN: 0080558003
Category : Technology & Engineering
Languages : en
Pages : 477

Get Book Here

Book Description
Approx.480 pagesApprox.480 pages

Author: Ahmad Fauzi Ismail
Publisher: Springer
ISBN: 3319010956
Category : Science
Languages : en
Pages : 340

Get Book Here

Book Description
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.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 97

Get Book Here

Book Description
The general objective of this project was to synthesize permselective membranes suitable for hydrogen separation from coal gas. The specific objectives were: (i) to synthesize membranes by chemical vapor deposition (CVD) of SiO[sub 2] or other oxides on porous support tubes, (ii) characterize the membranes by permeation measurements of various gases and by electron microscopy, and (iii) obtain information about the mechanism and kinetics Of SiO[sub 2] deposition, and model the process of membrane formation. Silica glass and certain other glasses, in dense (nonporous) form, are highly selective to hydrogen permeation. Since this high selectivity is accompanied by low permeability, however, a practical membrane must have a composite structure consisting of a thin layer of the active oxide supported on a porous tube or plate providing mechanical support. In this project the membranes were synthesized by chemical vapor deposition (CVD) of SiO[sub 2], TiO[sub 2], Al[sub 2]O[sub 3] and B[sub 2]O[sub 3] layers inside the walls of porous Vycor tubes (5 mm ID, 7 mm OD, 40 [Angstrom] mean pore diameter). Deposition of the oxide layer was carried out using the reaction of SiCl[sub 4] (or TiCl[sub 4], AlCl[sub 3], BCl[sub 3]) and water vapor at elevated temperatures. The porous support tube was inserted concentrically into a larger quartz tube and fitted with flow lines and pressure gauges. The flow of the two reactant streams was regulated by mass flow controllers, while the temperature was controlled by placing the reactor into a split-tube electric furnace.

Author: Rasel Das
Publisher: Materials Research Forum LLC
ISBN: 1644901633
Category : Technology & Engineering
Languages : en
Pages : 342

Get Book Here

Book Description
Various organic and synthetic polymers are important materials for the removal of organic and inorganic pollutants from wastewater and the separation of gases. The book discusses various types of membranes for microfiltration, ultrafiltration, nanofiltration, reverse osmosis, forward osmosis etc. A number of nanomaterials are available for the modification of polymeric membranes. Keywords: Polymeric Membrane, Water Purification, Water Softening, Water Desalination, Gas Separation, Osmosis Membranes, Microfiltration, Ultrafiltration, Nanofiltration, Carbon Nanotube, Nanosheets, MOFs, Porous Organic Cages, Titanium Dioxide, Zinc Oxide, Mesoporous Silica Nanoparticles, O2/N2 Separation, CO2/CH4 Separation, H2/N2 Separation.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 69

Get Book Here

Book Description
This project is a continuation of a previous DOE-UCR project (DE-FG22- 89PC89765) dealing with the preparation of silica membranes highly permselective to hydrogen at elevated temperatures, suitable for hydrogen separation from coal gas. The membranes prepared in the previous project had very high selectivity but relatively low permeance. Therefore, the general objectives of this project were to improve the permeance of these membranes and to obtain fundamental information about membrane structure and properties. The specific objectives were: (1) to explore new silylation reagents and reaction conditions with the purpose of reducing the thickness and increasing the permeance of silica membranes prepared by chemical vapor deposition (CVD), (2) to characterize the membrane structure, (3) to delineate mechanism and kinetics of deposition, (4) to measure the permeability of silica layers at different extents of deposition, and (5) to mathematically model the relationship between structure and deposition kinetics.