Open Access
Microporous and Mesoporous Materials
Zhi-Gang Gu,Alexander Pfriem,Sebastian Hamsch,Helmut Breitwieser,Jonas Wohlgemuth,Lars Heinke,Hartmut Gliemann,Christof W +7 more
- 01 Jan 2015
409
TL;DR: In this article, a vacuum-assisted liquid-vapor "flow-through" method was used to exchange Na-MFI disks with Ga 3+,Z n 2+, and Pt 2+ ions in the temperature range of 23-70 C and exchange times of 5-24 h.
read more
Abstract: Ion exchange of nanoporous (e.g., zeolite) membranes is of increasing importance in their applications as separation devices and catalytic reactors. Ion exchange processes in zeolite membranes are significantly limited by slow hydrated-ion transport rates and the low liquid-solid interfacial area available in com- parison to ion exchange of zeolites in powdered form, thereby leading to long membrane processing and regeneration times. Here, we consider ion exchange processes in zeolite membranes in more detail, and show the much higher efficacy of a vacuum-assisted liquid-vapor 'flow-through' method in compar- ison to both the conventional 'immersion/counter-diffusion' method as well as a liquid-liquid flow- through method. Na-MFI zeolite disk membranes, made by both in situ and seeded growth, were ion- exchanged with Ga 3+ ,Z n 2+ , and Pt 2+ ions in the temperature range of 23-70 C and exchange times of 5-24 h. The penetration of these ions into the zeolite membranes was investigated in detail by energy- dispersive X-ray (EDX) spectroscopy. Surprisingly, the quantity of exchanged ions in the membranes via the vacuum-assisted 'flow-through' technique is found to exceed that achieved by the other two methods by up to a factor of ten, with the liquid-liquid technique being the least efficient. Higher tem- peratures and longer ion exchange times increased the ion exchange efficiency in the vacuum-assisted method. Chemical analysis of the condensed permeate solution by inductively-coupled plasma (ICP) mass spectrometry revealed that both the original Na
read more
Chat with Paper
AI Agents for this Paper
Find similar papers on Google Scholar, PubMed and Arxiv
Write a critical review of this paper
Analyze citations of this paper to find unaddressed research gaps
Citations
Optimum conditions for adsorptive storage.
Suresh K. Bhatia,Alan L. Myers +1 more
TL;DR: It is demonstrated that for maximum delivery of the gas the optimum adsorbent must be homogeneous, and that introduction of heterogeneity, such as by ball milling, irradiation, and other means, can only provide small increases in physisorption-related delivery for hydrogen.
Catalysis in a Cage: Condition-Dependent Speciation and Dynamics of Exchanged Cu Cations in SSZ-13 Zeolites
Christopher Paolucci,Atish A. Parekh,Ishant Khurana,John R. Di Iorio,Hui Li,Jonatan D. Albarracin Caballero,Arthur J. Shih,Trunojoyo Anggara,W. Nicholas Delgass,Jeffrey T. Miller,Fabio H. Ribeiro,Rajamani Gounder,William F. Schneider +12 more
TL;DR: Experimental and theory together reveal that the Cu sites respond sensitively to exposure conditions, and in particular that Cu species are solvated and mobilized by NH3 under SCR conditions.
679
Challenges in biocatalysis for enzyme-based biofuel cells.
TL;DR: It appears to be reasonable to expect that progress in nanostuctured biocatalysts will play a critical role in overcoming the major obstacles in the development of powerful biofuel cells.
587
In situ synthesis of thin zeolitic-imidazolate framework ZIF-8 membranes exhibiting exceptionally high propylene/propane separation.
Hyuk Taek Kwon,Hae-Kwon Jeong +1 more
TL;DR: A simple one step in situ method based on a counter-diffusion concept to prepare well-intergrown ZIF-8 membranes with significantly enhanced microstructure, resulting in exceptionally high separation performance toward propylene over propane.
545
Porous carbon nanosheets: Synthetic strategies and electrochemical energy related applications
TL;DR: In this article, a review article comprehensively summarizes the recent developments in synthetic methods, including the hard template strategy, soft template strategy and template-free strategy for successful preparation of carbon nanosheets.
398
References
Ordered mesoporous molecular sieves synthesized by a liquid-crystal template mechanism
TL;DR: In this paper, the synthesis of mesoporous inorganic solids from calcination of aluminosilicate gels in the presence of surfactants is described, in which the silicate material forms inorganic walls between ordered surfactant micelles.
16.1K
Design and synthesis of an exceptionally stable and highly porous metal-organic framework
TL;DR: In this article, an organic dicarboxylate linker is used in a reaction that gives supertetrahedron clusters when capped with monocarboxyates.
•Book
Introduction to chemical engineering thermodynamics
J. M. Smith
- 01 Jan 1949
TL;DR: In this article, the second law of thermodynamics is used to describe the properties of pure fluids and their properties in the context of flow process analysis, and a discussion of the application of thermodynamic analysis of processes can be found.
5.1K
•Book
Ionic Liquids in Synthesis
Peter Wasserscheid,Tom Welton +1 more
- 01 Jan 2002
TL;DR: The early years of Ionic liquid production were covered in this article, where a new generation of soluble supports for Supported Organic Synthesis (SPOS) was proposed. But this support was not applied to the task-specific Ionic liquids.
•Book
Adsorption by Powders and Porous Solids: Principles, Methodology and Applications
Françoise Rouquerol,Jean Rouquerol,Kenneth S. W. Sing +2 more
- 05 Oct 1998
TL;DR: In this paper, the authors provide an introductory review of the various theoretical and practical aspects of adsorption by powders and porous solids with particular reference to materials of technological importance.
4K