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Showing 1 to 20 of 25 for “"Gas Separations"”.
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Polymer Aluminophosphate Mixed Matrix Membranes for Gas Separations
… polymer matrix decrease the permeability of all gases through that membrane. Our objective was to explore the effects on transport when a microporous layered aluminophosphate was added to a polymer matrix. The clay like layered aluminophosphate used contains sheets with 8MR ring openings in the …
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Free Volume Manipulation Techniques of Polymer Membranes for Gas Separations
Gas separations are ubiquitous in today’s industries and society, playing a role in many key applications such as oxygen generation for medical procedures and natural gas separations for power generation and petrochemicals. In the United States, separation processes consume about 16 quadrillion BTU …
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High Permeability/High Diffusivity Mixed Matrix Membranes For Gas Separations
The vast majority of commercial gas separation membrane systems are polymeric because of processing feasibility and cost. However, polymeric membranes designed for gas separations have been known to have a trade-off between permeability and selectivity as shown in Robeson's upper bound curves. The …
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The Synthesis of Anionic and Amine Containing Polymers for Potential Gas Separations
With the growth of industry, the need for gas separation has increased. In the last few decades, various types of polymeric gas separation membranes have been developed due to their advantages of energy-efficiency, easy operation processes, and low cost on assembly and maintenance. While it is …
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Mixed-gas Transport in Microporous Polymer Derivatives for Energy-Efficient Gas Separations
Over the past forty years, membrane-based gas separations have emerged as a promising alternative to energy-intensive separation processes such as amine absorption and cryogenic distillation. However, a trade-off between permeability and selectivity as well as issues of decreased performance at …
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Post-Synthetic Chemical and Morphological Modifications of Polymer Membranes for Gas Separations
… became potential candidates for next-generation gas separation membrane materials. Over the past two decades, this potential has sparked extensive membrane material development research, resulting in a library of microporous polymers. However, despite these significant advancements in developing …
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Fabrication and Characterization of Polyimide-based Mixed Matrix Membranes for Gas Separations
… voids between the two components. While simple gases such as O2 and N2 followed effective permeabilities predicted by mixing theories, polar gases such as CO₂ did not. The second system fabricated used the same polyimide with amine-functionalized zeolite L. This zeolite differs from ZSM-2 in …
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Highly productive ester crosslinkable composite hollow fiber membranes for aggressive natural gas separations
… approach challenging, especially for large-scale gas separations which require large membrane areas with high feed pressures. Dual-layer hollow fiber spinning can be used to reduce the cost of membrane production by integrating a low-cost supporting core polymer with the expensive crosslinkable …
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3D-printed adsorbents for gas separations: A material development, kinetic assessment, and process performance investigation
“Adsorbent materials are promising for various gas purification processes, however, forming them into structured contactors is paramount in enhancing mass transfer properties and reducing pressure losses. In this research, various adsorbents were engineered into structured contactors with 3D …
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Assemblies of Metal-Organic Polyhedra: Synthesis, Properties and Characterization
… PEBAX polymer were created for usage in CO2/N2 gas separations. Overall, the thesis provides a reference for exploiting novel properties of MOPs.
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Coordination Cages as a Scaffold for Permanently Porous Liquids
… in applications such as extractions and gas separations. We present the first adaptation of coordination cages into porous liquids by functionalizing a series coordination cages of different sizes and structures with alkylimidazolium and PEG-imidazolium moieties. The …
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Polymer-Metal–Organic Framework (MOF) Mixed-Matrix Membranes for Gas Separation Applications
… of significant interest for membrane-based gas separations. Mixed-matrix membranes (MMMs) formed by incorporating MOF particles into polymers have attracted significant attention because these composite systems can potentially surpass the separation performance of pure polymers alone. …
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Molten Alkali Metal Borate/Carbonate Salts for High Temperature CO₂ Capture and Electrochemical Conversion
… and as an alternative to current greenhouse gas-intensive CNT synthesis pathways. Prior work in this field has primarily focused on the effects of parameters such as alternate chemistries, electrolyte additives, and electrode composition on the achievable products and energetic demands. This …
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Gas Separation Using Nanoporous Single-Layer Graphene Membranes
… 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 …
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Leveraging Competitive Sorption in Microporous Polymer Membranes to Enhance Gas Separation Performance
Chemical separations account for roughly half of the United States’ industrial energy consumption, 49% of which is attributed to distillation alone. Membrane-based systems, on the other hand, offer a more energy-efficient alternative to conventional separation processes because they do not require …
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Evaluating the Effect of Composition, Structure and Functionality on Atmospheric CO2 Adsorption in Porous Solid Sorbents
… dioxide (CO2) is the most abundant greenhouse gas in the atmosphere, and it is estimated to be responsible for approximately two thirds of the total global warming effect caused by anthropogenic gas emissions. Meeting the Paris Agreement objective of temperature increases well below 2°C above …
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Fabrication and Gas Permeation Studies on Polyimide/Layered-Aluminum Phosphate Nanocomposite Membranes
… The objective of this study was to examine if gas separation performance could be improved by introducing a layered nanopourous aluminum phosphate with a large aspect ratio into a polymeric matrix. The aluminum phosphate has eight membered rings, which could potentially serve as a size …
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Functionalized High Aspect Ratio Cellulose Nanocrystal Filled Composites for Gas and Liquid Separations
… is a ubiquitous feature of industry, and these separations are necessary for every facet of life down to the simple functions of breathing clean air and drinking potable water. These chemical separations account for a large portion of the total energy use both in the United States and globally. …
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Microporous polymeric membranes via melt processing
… high temperature environments for liquid and gas separations. The fabrication process developed here is shown to be a promising technique for producing mesoporous and microporous membranes. The process has several potential advantages over other membrane fabrication processes, i.e.: no …
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Using Data-Driven Models to Understand Transition Metal Catalyst Energy Landscapes and Metal-Organic Framework Stability
… have been developed for various applications in gas separations, sensing, and catalysis. In practice, we must activate a MOF and remove solvent from its pores to render it porous and usable. Simultaneously, the MOF must also be stable under the thermal conditions. Although the tailored metal …
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