subject:(Gas separations)

Texas A&M University

1. Liu, Ting. Hybrid Membranes for Light Gas Separations.

Degree: MS, Chemical Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10722

► Membrane separations provide a potentially attractive technology over conventional processes due to their advantages, such as low capital cost and energy consumption. The goal of… (more)

Subjects/Keywords: gas separations; FTM; dendrimer; Cu(I); olefin/paraffin separations

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APA (6^th Edition):

Liu, T. (2012). Hybrid Membranes for Light Gas Separations. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10722

Chicago Manual of Style (16^th Edition):

Liu, Ting. “Hybrid Membranes for Light Gas Separations.” 2012. Masters Thesis, Texas A&M University. Accessed April 15, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10722.

MLA Handbook (7^th Edition):

Liu, Ting. “Hybrid Membranes for Light Gas Separations.” 2012. Web. 15 Apr 2021.

Vancouver:

Liu T. Hybrid Membranes for Light Gas Separations. [Internet] [Masters thesis]. Texas A&M University; 2012. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10722.

Council of Science Editors:

Liu T. Hybrid Membranes for Light Gas Separations. [Masters Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10722

Texas A&M University

2. Lee, Moon Joo. Toward High-Throughput Zeolitic Imidazolate Framework ZIF-8 Membranes for Propylene/Propane Separation.

Degree: PhD, Chemical Engineering, 2018, Texas A&M University

URL: http://hdl.handle.net/1969.1/173498

► Separations of light olefin/paraffin, e.g., ethylene/ethane and propylene/propane, are crucial in the petrochemical industries. However, conventional separation processes, e.g., cryo-distillation, require tremendous amounts of energy… (more)

▼ Separations of light olefin/paraffin, e.g., ethylene/ethane and propylene/propane, are crucial in the petrochemical industries. However, conventional separation processes, e.g., cryo-distillation, require tremendous amounts of energy and high capital cost. Membrane-based separations are a promising alternative to conventional separation processing, however, because of the limited separation capability of current membrane materials, such as polymers, the development of advanced membrane materials is highly desirable. Zeolitic-imidazolate frameworks (ZIFs) are nanoporous crystalline materials with well-defined ultramicropores (< 5 Å), thereby attractive for membrane-based gas separations. A prototypical ZIF-8 have shown unprecedented propylene/propane separation capabilities because of its effective aperture size of ca. 4 Å, which is in between the sizes of propylene and propane. However, some challenges are impeding their commercial applications; slow batch processes, expensive and fragile ceramic supports, long-term stability, lack of general processing methods. A significant improvement in the productivity (i.e., throughput) of polycrystalline ZIF-8 membranes is required to overcome the current challenges of membrane processing. Therefore, the membrane productivity can be enhanced by increasing membrane area and substantially reducing membrane thickness. In this dissertation, advanced membrane processing techniques toward high flux ZIF-8 membranes for their practical propylene/propane separation are proposed. Two unique membrane fabrication methods, in situ counter diffusion method and microwave-seeding and secondary growth method, previously developed from our group were chosen and thoroughly studied in the overall study. Firstly, the separation performances of ZIF-8 membranes depend on synthesis method, for propylene/propane separation, are studied. Defect-density of ZIF-8 powders and membranes were characterized with a series of characterizations. Post-synthetic treatments effectively stabilized less stable membranes. Secondly, high propylene-throughput ZIF-8 membrane was prepared by a novel approach for propylene/propane separation. Propylene-selective layer thickness was systematically reduced via post-synthetic linker exchange of ZIF-8 membranes. The resulting linker-exchanged ZIF-8 membranes exhibited significant increase in propylene permeance by four times. Lastly, scalable ZIF-8 membrane processing method on polymeric hollow fiber substrates is introduced. The unique microwave-assisted seeding prepared was capable of ultrathin ZIF-8 membranes formation. Propylene/propane separation performance of resulting ZIF-8 membranes was performed. Advisors/Committee Members: Jeong, Hae-Kwon (advisor), Zhou, Hongcai Joe (committee member), Elabd, Yossef (committee member), Wilhite, Benjamin (committee member).

Subjects/Keywords: Membrane gas separations; MOFs; ZIFs; Olefin/paraffin separations; Ultrathin membranes; Membrane processing

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APA (6^th Edition):

Lee, M. J. (2018). Toward High-Throughput Zeolitic Imidazolate Framework ZIF-8 Membranes for Propylene/Propane Separation. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/173498

Chicago Manual of Style (16^th Edition):

Lee, Moon Joo. “Toward High-Throughput Zeolitic Imidazolate Framework ZIF-8 Membranes for Propylene/Propane Separation.” 2018. Doctoral Dissertation, Texas A&M University. Accessed April 15, 2021. http://hdl.handle.net/1969.1/173498.

MLA Handbook (7^th Edition):

Lee, Moon Joo. “Toward High-Throughput Zeolitic Imidazolate Framework ZIF-8 Membranes for Propylene/Propane Separation.” 2018. Web. 15 Apr 2021.

Vancouver:

Lee MJ. Toward High-Throughput Zeolitic Imidazolate Framework ZIF-8 Membranes for Propylene/Propane Separation. [Internet] [Doctoral dissertation]. Texas A&M University; 2018. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/1969.1/173498.

Council of Science Editors:

Lee MJ. Toward High-Throughput Zeolitic Imidazolate Framework ZIF-8 Membranes for Propylene/Propane Separation. [Doctoral Dissertation]. Texas A&M University; 2018. Available from: http://hdl.handle.net/1969.1/173498

University of California – Berkeley

3. Xiao, Dianne Jing. Metal–Oxo and Dioxygen Chemistry in Metal–Organic Frameworks: Applications in Catalysis and Gas Separations.

Degree: Chemistry, 2016, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/14f2b0xj

► The work herein describes progress towards using metal–organic frameworks as scaffolds for stabilizing metal–oxo and dioxygen species, and their application in hydrocarbon oxidation catalysis and… (more)

▼ The work herein describes progress towards using metal–organic frameworks as scaffolds for stabilizing metal–oxo and dioxygen species, and their application in hydrocarbon oxidation catalysis and O2/N2 separations. Metal–organic frameworks are a class of highly porous and functionally versatile crystalline solids consisting of inorganic cations or clusters bridged by organic linkers. They are attractive as solid supports for metal–oxo and dioxygen chemistry for many reasons, including the presence of well-defined, site-isolated metal centers with highly tunable local and outer coordination spheres.Chapter 1 provides an introduction to the electronic structure, reactivity, and biological relevance of metal–oxo and dioxygen species, with a particular emphasis on iron and cobalt. In addition, a brief historical overview of the development of biomimetic iron–oxo, iron–dioxygen, and cobalt–dioxygen chemistry, with selected molecular and heterogenous examples, is provided. The chapter concludes with a summary of the methods currently used to install coordinatively-unsaturated redox-active metal sites into metal–organic frameworks. A perspective on the potential of metal–organic frameworks in metal–oxo and dioxygen chemistry is given.Chapter 2 describes an initial foray into metal–organic framework-supported iron–oxo chemistry. Specifically, the nitrous oxide activation and hydrocarbon oxidation reactivity of the coordinatively-unsaturated iron(II) sites in the metal-organic frameworks Fe2(dobdc) and Fe0.1Mg1.9(dobdc) (dobdc4– = 2,5-dioxido-1,4-benzenedicarboxylate) is detailed. In the presence of N2O, the latter framework is able to selectively and catalytically convert ethane to ethanol upon mild heating. Structural and spectroscopic characterization of the initial iron(II)–N2O adduct and an iron(III)-hydroxide decay product, reactivity studies, and detailed electronic structure calculations strongly suggest that the active oxidant in this system is a high-spin, S = 2 iron(IV)–oxo. This rare electronic structure is a direct result of the weak ligand field imparted by the dobdc4– ligand.In addition to primary coordination sphere properties such as a weak ligand field, longer-range pore-environment effects could also become a powerful parameter in metal–organic framework catalyst design. Chapter 3 explores this idea in the context of solution-phase cyclohexane oxidation in the biphenyl and terphenyl expanded Fe2(dobdc) derivatives. A three-fold enhancement of the alcohol:ketone (A:K) ratio and an order of magnitude increase in turnover number is observed by simply altering the framework pore diameter and installing nonpolar, hydrophobic functional groups near the iron center. The increase in A:K selectivity is attributed to an increased affinity of the pore walls for cyclohexane, which may help increase its local concentration near the iron site.Chapter 4 departs from iron–oxo chemistry and oxidation catalysis, focusing instead on cobalt–dioxygen binding for O2/N2 separation applications. Specifically, this chapter details…

Subjects/Keywords: Chemistry; Catalysis; Gas separations; Iron–oxo; Metal–organic frameworks

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APA (6^th Edition):

Xiao, D. J. (2016). Metal–Oxo and Dioxygen Chemistry in Metal–Organic Frameworks: Applications in Catalysis and Gas Separations. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/14f2b0xj

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Xiao, Dianne Jing. “Metal–Oxo and Dioxygen Chemistry in Metal–Organic Frameworks: Applications in Catalysis and Gas Separations.” 2016. Thesis, University of California – Berkeley. Accessed April 15, 2021. http://www.escholarship.org/uc/item/14f2b0xj.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Xiao, Dianne Jing. “Metal–Oxo and Dioxygen Chemistry in Metal–Organic Frameworks: Applications in Catalysis and Gas Separations.” 2016. Web. 15 Apr 2021.

Vancouver:

Xiao DJ. Metal–Oxo and Dioxygen Chemistry in Metal–Organic Frameworks: Applications in Catalysis and Gas Separations. [Internet] [Thesis]. University of California – Berkeley; 2016. [cited 2021 Apr 15]. Available from: http://www.escholarship.org/uc/item/14f2b0xj.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Xiao DJ. Metal–Oxo and Dioxygen Chemistry in Metal–Organic Frameworks: Applications in Catalysis and Gas Separations. [Thesis]. University of California – Berkeley; 2016. Available from: http://www.escholarship.org/uc/item/14f2b0xj

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

4. Lewis, Jeremy. Enhancing Liquid And Gas Separation With Activated Carbon Mixed-Matrix Membranes.

Degree: MEngr, Chemical Engineering, 2019, University of North Dakota

URL: https://commons.und.edu/theses/2468

► Mixed matrix membranes are one class of membrane material that are an especially promising separation media. By adding a particle phase to a matrix… (more)

Subjects/Keywords: activated carbon; dye filtration; gas separation; Mixed matrix membranes; nanocomposites; separations

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APA (6^th Edition):

Lewis, J. (2019). Enhancing Liquid And Gas Separation With Activated Carbon Mixed-Matrix Membranes. (Masters Thesis). University of North Dakota. Retrieved from https://commons.und.edu/theses/2468

Chicago Manual of Style (16^th Edition):

Lewis, Jeremy. “Enhancing Liquid And Gas Separation With Activated Carbon Mixed-Matrix Membranes.” 2019. Masters Thesis, University of North Dakota. Accessed April 15, 2021. https://commons.und.edu/theses/2468.

MLA Handbook (7^th Edition):

Lewis, Jeremy. “Enhancing Liquid And Gas Separation With Activated Carbon Mixed-Matrix Membranes.” 2019. Web. 15 Apr 2021.

Vancouver:

Lewis J. Enhancing Liquid And Gas Separation With Activated Carbon Mixed-Matrix Membranes. [Internet] [Masters thesis]. University of North Dakota; 2019. [cited 2021 Apr 15]. Available from: https://commons.und.edu/theses/2468.

Council of Science Editors:

Lewis J. Enhancing Liquid And Gas Separation With Activated Carbon Mixed-Matrix Membranes. [Masters Thesis]. University of North Dakota; 2019. Available from: https://commons.und.edu/theses/2468

University of Colorado

5. Koenig, Steven Paul. Graphene Membranes: Mechanics, Adhesion, and Gas Separations.

Degree: PhD, Mechanical Engineering, 2013, University of Colorado

URL: https://scholar.colorado.edu/mcen_gradetds/68

► This thesis examines the mechanical, and adhesive properties of graphene and explores using graphene as a gas separation membrane. A pressurized blister test was… (more)

▼ This thesis examines the mechanical, and adhesive properties of graphene and explores using graphene as a gas separation membrane. A pressurized blister test was used to measure both the in-plane mechanical properties and adhesion energy of monolayer and few layer graphene suspended over a circular cavity in silicon oxide. The adhesion energy between graphene and silicon oxide was found to be 0.45 ± 0.02 J m-2 for monolayer graphene and 0.31 ± 0.03 J m-2 for samples containing two to five graphene layers. These values are larger than the adhesion energies measured in typical micromechanical structures and are comparable to solid-liquid adhesion energies. We attribute this to the extreme flexibility of graphene, which allows is to conform to the topography of even the smoothest substrates, thus making its interaction with the substrate more liquid like than solid like. In addition we found that the in-plane mechanical properties are consistent with previously reported values. We also show that ultraviolet-induced oxidative etching can create pores in micrometer-sized graphene membranes, and the resulting membranes can be used as molecular sieves. A pressurized blister test, similar to that used for testing the mechanical properties, and mechanical resonance are used to measure the transport of a range of gases (H₂, CO₂, Ar, N₂, CH₄, and SF₆) through the pores. The experimentally measured leak rate, separation factors, and Raman spectrum agree well with models based on effusion through a small number of angstrom-sized pores. Lastly, we work toward creating large scale gas separation membranes from chemical vapor deposition (CVD) grown graphene films. CVD graphene films are grown on copper foils and transferred to a polymer support or suspended over openings in copper. Films are measured in a time lag permeation apparatus to get gas permeation and ideal gas separation factors. Advisors/Committee Members: Joseph Scott Bunch, Todd W. Murry, John Pellegrino, Jiangliang Xiao, Mark P. Stoykovich.

Subjects/Keywords: Adhesion; Gas Separations; Graphene; Mechanics; Molecular Sieving; Mechanical Engineering

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APA (6^th Edition):

Koenig, S. P. (2013). Graphene Membranes: Mechanics, Adhesion, and Gas Separations. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/mcen_gradetds/68

Chicago Manual of Style (16^th Edition):

Koenig, Steven Paul. “Graphene Membranes: Mechanics, Adhesion, and Gas Separations.” 2013. Doctoral Dissertation, University of Colorado. Accessed April 15, 2021. https://scholar.colorado.edu/mcen_gradetds/68.

MLA Handbook (7^th Edition):

Koenig, Steven Paul. “Graphene Membranes: Mechanics, Adhesion, and Gas Separations.” 2013. Web. 15 Apr 2021.

Vancouver:

Koenig SP. Graphene Membranes: Mechanics, Adhesion, and Gas Separations. [Internet] [Doctoral dissertation]. University of Colorado; 2013. [cited 2021 Apr 15]. Available from: https://scholar.colorado.edu/mcen_gradetds/68.

Council of Science Editors:

Koenig SP. Graphene Membranes: Mechanics, Adhesion, and Gas Separations. [Doctoral Dissertation]. University of Colorado; 2013. Available from: https://scholar.colorado.edu/mcen_gradetds/68

University of Colorado

6. Singh, Zoban Veer. Design and Evaluation of New Mixed-Matrix Membranes for CO2/CH4 Separations.

Degree: PhD, 2017, University of Colorado

URL: https://scholar.colorado.edu/chbe_gradetds/110

► Many polymeric materials are mechanically robust and thus can be used to form membranes for CO₂/CH₄ separations. Most of these polymers, however, do not… (more)

Subjects/Keywords: CH4; CO2; gas separations; membranes; mixed-matrix membranes; Chemical Engineering

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APA (6^th Edition):

Singh, Z. V. (2017). Design and Evaluation of New Mixed-Matrix Membranes for CO2/CH4 Separations. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/chbe_gradetds/110

Chicago Manual of Style (16^th Edition):

Singh, Zoban Veer. “Design and Evaluation of New Mixed-Matrix Membranes for CO2/CH4 Separations.” 2017. Doctoral Dissertation, University of Colorado. Accessed April 15, 2021. https://scholar.colorado.edu/chbe_gradetds/110.

MLA Handbook (7^th Edition):

Singh, Zoban Veer. “Design and Evaluation of New Mixed-Matrix Membranes for CO2/CH4 Separations.” 2017. Web. 15 Apr 2021.

Vancouver:

Singh ZV. Design and Evaluation of New Mixed-Matrix Membranes for CO2/CH4 Separations. [Internet] [Doctoral dissertation]. University of Colorado; 2017. [cited 2021 Apr 15]. Available from: https://scholar.colorado.edu/chbe_gradetds/110.

Council of Science Editors:

Singh ZV. Design and Evaluation of New Mixed-Matrix Membranes for CO2/CH4 Separations. [Doctoral Dissertation]. University of Colorado; 2017. Available from: https://scholar.colorado.edu/chbe_gradetds/110

University of Minnesota

7. Xue, Feng. Development of Novel Porous Materials and Thin Membranes For Gas Separations.

Degree: PhD, Material Science and Engineering, 2020, University of Minnesota

URL: http://hdl.handle.net/11299/216178

► The development of high-flux, high-selectivity, and low-cost membranes has the potential to improve the energy efficiency in the chemical industry by reducing the reliance on… (more)

▼ The development of high-flux, high-selectivity, and low-cost membranes has the potential to improve the energy efficiency in the chemical industry by reducing the reliance on energy-intensive separation processes, such as distillation. To achieve this goal, novel porous materials and membrane fabrication methods are being increasingly sought after. Metal-organic frameworks (MOFs) are a new type of microporous materials with tunable pore structures suitable for gas separations. However, the high manufacturing cost and industrially-unattractive throughput hinder the industrial applications of MOF membranes. Fabrication of thin membranes with high throughput has the potential to overcome this barrier. This dissertation focuses on developing synthesis methods for thin MOF membranes by using two-dimensional (2D) MOF nanosheets and an all-vapor-phase zeolitic imidazolate frameworks (ZIFs) membrane synthesis process named ligand-induced permselectivation (LIPS). Crystal growth strategies for 2D MOFs were developed that yield Zn(Bim)OAc MOF nanosheets with desirable aspect ratio and uniformity for membrane formation. Using the Zn(Bim)OAc nanosheets, uniform coatings were successfully prepared on porous supports by vacuum filtration. A novel vapor growth method combining the support surface modification and ligand vapor treatment was developed to transform the nanosheet deposits into thin propylene-selective membranes. In addition, in an effort to reduce the membrane cost by using low-cost polymers, porous Cu(BDC) MOF nanosheets were incorporated into polymer matrices to form mixed matrix membranes that exhibited significantly improved performance for CO2/N2 separation. Besides solution processing of MOF membranes, a novel, well-controlled and cost-effective all-vapor-synthesis LIPS method with a combination of atomic layer deposition (ALD) and ligand vapor treatment was investigated. It was demonstrated that an ALD processing condition allowing a thin non-permeable ZnO deposit formation, as well as efficient ZnO-to-ZIFs conversion during ligand vapor treatment are very critical to realize consistent high membrane performance. With optimized ALD parameters, support and ligand properties, the membranes exhibit superior separation performance, with propylene permeance above 1.3 ×10-7 mol m-2 s-1 Pa-1 and propylene/propane selectivity above 60, which is highly promising for industrial applications.

Subjects/Keywords: Gas separations; Membranes; Metal-organic frameworks; Nanosheets; Vapor synthesis

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APA (6^th Edition):

Xue, F. (2020). Development of Novel Porous Materials and Thin Membranes For Gas Separations. (Doctoral Dissertation). University of Minnesota. Retrieved from http://hdl.handle.net/11299/216178

Chicago Manual of Style (16^th Edition):

Xue, Feng. “Development of Novel Porous Materials and Thin Membranes For Gas Separations.” 2020. Doctoral Dissertation, University of Minnesota. Accessed April 15, 2021. http://hdl.handle.net/11299/216178.

MLA Handbook (7^th Edition):

Xue, Feng. “Development of Novel Porous Materials and Thin Membranes For Gas Separations.” 2020. Web. 15 Apr 2021.

Vancouver:

Xue F. Development of Novel Porous Materials and Thin Membranes For Gas Separations. [Internet] [Doctoral dissertation]. University of Minnesota; 2020. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/11299/216178.

Council of Science Editors:

Xue F. Development of Novel Porous Materials and Thin Membranes For Gas Separations. [Doctoral Dissertation]. University of Minnesota; 2020. Available from: http://hdl.handle.net/11299/216178

Georgia Tech

8. Achoundong, Carine Saha Kuete. Engineering economical membrane materials for aggressive sour gas separations.

Degree: PhD, Chemical and Biomolecular Engineering, 2013, Georgia Tech

URL: http://hdl.handle.net/1853/50289

► The goal is of this project was to identify principles to guide the development of high performance dense film membranes for natural gas sweetening using… (more)

▼ The goal is of this project was to identify principles to guide the development of high performance dense film membranes for natural gas sweetening using hydrogen sulfide and carbon dioxide gas mixtures as models under aggressive sour gas feed conditions. To achieve this goal, three objectives were developed to guide this research. The first objective was to study the performance of cellulose acetate (CA) and an advanced crosslinkable polyimide (PDMC) dense film membrane for H₂S separation from natural gas. The second objective was to engineer those polymers to produce membrane materials with superior performance as measured by efficiency, productivity, and plasticization resistance, and the third objective was to determine the separation performance of these engineered membrane materials under more aggressive, realistic natural gas feeds, and to perform a detailed transport analysis of the factors that impact their performance. Work on the first objective showed that in neat CA, penetrant transport is controlled by both the solubility and mobility selectivity, with the former being more dominant, leading to a high overall CO₂/CH₄ (33) and H₂S/CH₄ (35) ideal selectivities. However, in uncrosslinked PDMC, H₂S/CH₄ selectivity favored sorption only, whereas CO₂/CH₄ selectivity favored both mobility and sorption selectivity, leading to a high CO₂/CH₄ (37) but low H₂S/CH₄ (12) ideal selectivities. However, the latter polymer showed more plasticization resistance for CO₂. In the second objective, both materials were engineered. A new technique referred to as “GCV-Modification” was introduced in which cellulose acetate was grafted using vinyltrimethoxysilane (VTMS), then hydrolyzed and condensed to form a polymer network. PDMC was also covalently crosslinked to enhance its performance. GCV-Modified CA showed significant performance improvements for H₂S and CO₂ removal; the permeability of CO₂ and H₂S were found to be 139 and 165 Barrer, respectively, which represented a 30X and 34X increase compared to the pristine CA polymer. The H₂S/CH₄ and CO₂/CH₄ ideal selectivities were found to be 39 and 33, respectively. Crosslinked PDMC showed a higher CO₂/CH₄ selectivity of 38 with a better plasticization resistance for CO₂ and H₂S. In the third objective, these materials were tested under aggressive ternary mixtures of H₂S/CO₂/CH₄ with both vacuum and nonvacuum downstream. Even under aggressive feed conditions, GCV-Modified CA showed better performance vs. PDMC, and it remained were fairly stable, making it a potential candidate for aggressive sour gas separations, not only because of its significantly higher productivity, which will help decrease the surface area needed for separation, thereby reducing operating costs, but also because of the lower cost of the raw material GCV-Modified CA compared to PDMC. Advisors/Committee Members: Koros, William J. (advisor), Jacob, Karl (committee member), Meredith, Carson (committee member), Nair, Sankar (committee member), Walton, Krista (committee member).

Subjects/Keywords: Acid gas; Sour gas; Membrane gas separations; Polymer membrane; Cellulose acetate; PDMC; Natural gas; Membrane separation; Hydrogen sulfide; Carbon dioxide

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APA (6^th Edition):

Achoundong, C. S. K. (2013). Engineering economical membrane materials for aggressive sour gas separations. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/50289

Chicago Manual of Style (16^th Edition):

Achoundong, Carine Saha Kuete. “Engineering economical membrane materials for aggressive sour gas separations.” 2013. Doctoral Dissertation, Georgia Tech. Accessed April 15, 2021. http://hdl.handle.net/1853/50289.

MLA Handbook (7^th Edition):

Achoundong, Carine Saha Kuete. “Engineering economical membrane materials for aggressive sour gas separations.” 2013. Web. 15 Apr 2021.

Vancouver:

Achoundong CSK. Engineering economical membrane materials for aggressive sour gas separations. [Internet] [Doctoral dissertation]. Georgia Tech; 2013. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/1853/50289.

Council of Science Editors:

Achoundong CSK. Engineering economical membrane materials for aggressive sour gas separations. [Doctoral Dissertation]. Georgia Tech; 2013. Available from: http://hdl.handle.net/1853/50289

Texas A&M University

9. Ramu, Gokula Krishnan. Effect of Different Parameters on the Microstructure and Performance of ZIF-8 Membranes.

Degree: MS, Chemical Engineering, 2016, Texas A&M University

URL: http://hdl.handle.net/1969.1/159004

► Metal-Organic Frameworks (MOFs) are nanoporous materials comprising of metal nodes coordinated to organic ligands. They exhibit regular crystal lattice structures with well-defined pores. Owing to… (more)

▼ Metal-Organic Frameworks (MOFs) are nanoporous materials comprising of metal nodes coordinated to organic ligands. They exhibit regular crystal lattice structures with well-defined pores. Owing to the ease with which the organic groups can be given different chemical functionalities, MOFs display highly flexible surface chemistry and pore sizes. This makes them suitable for their application as gas separation membranes. Zeolitic-Imidazolate Frameworks (ZIFs), a sub-class of MOFs, have pore sizes in the range of C3-C6 hydrocarbons, and in particular ZIF-8 (pore size 3.4Å), can be used for the industrially important propylene/propane separation. Because heterogeneous nucleation and growth of ZIF-8 crystals on the ceramic supports is not favored, their synthesis as membranes is complicated and involves multiple steps. Of the different synthesis techniques, the microwave-assisted seeding followed by the secondary growth is one of the most effective because of strong attachment of seed crystals to the supports achieved. The microstructure, and consequently, performance of membranes grown by this method is highly sensitive to different parameters and a systematic study of some of these will help to identify the best microstructure possible, reduce synthesis time, and improve reproducibility. Some of the parameters studied are different metal salt sources, aging of precursor solutions, post-synthetic activation time and membrane performance under high pressure and temperature. ZIF-8 seed layers and membranes were synthesized using the same recipe but different zinc salts to investigate the effect of different zinc metal sources on both seed layer and membrane performance and morphology. It was found that ZIF-8 membranes from zinc nitrate based seed layers had the best performance possibly due to better grain boundaries. Zinc nitrate-based ZIF-8 membranes showed good propylene/propane separation performance without any structural degradation when tested under harsher pressure and temperature (~ 7 bar and 100 ⁰C) conditions. Reduction in total synthesis time along with significant improvement in membrane performance was achieved by reducing the post synthesis activation time and using aged precursor solutions. Advisors/Committee Members: Jeong, Hae-Kwon (advisor), Akbulut, Mustafa (committee member), Yu, Choongho (committee member).

Subjects/Keywords: Gas separations; Zeolitic Imidazolate Frameworks; Zinc salt effect; One-step synthesis; High pressure performance

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APA (6^th Edition):

Ramu, G. K. (2016). Effect of Different Parameters on the Microstructure and Performance of ZIF-8 Membranes. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/159004

Chicago Manual of Style (16^th Edition):

Ramu, Gokula Krishnan. “Effect of Different Parameters on the Microstructure and Performance of ZIF-8 Membranes.” 2016. Masters Thesis, Texas A&M University. Accessed April 15, 2021. http://hdl.handle.net/1969.1/159004.

MLA Handbook (7^th Edition):

Ramu, Gokula Krishnan. “Effect of Different Parameters on the Microstructure and Performance of ZIF-8 Membranes.” 2016. Web. 15 Apr 2021.

Vancouver:

Ramu GK. Effect of Different Parameters on the Microstructure and Performance of ZIF-8 Membranes. [Internet] [Masters thesis]. Texas A&M University; 2016. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/1969.1/159004.

Council of Science Editors:

Ramu GK. Effect of Different Parameters on the Microstructure and Performance of ZIF-8 Membranes. [Masters Thesis]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/159004

University of Toledo

10. CHE MAT, NORFAMILA BINTI. Membrane Process Design for Post-Combustion Carbon Dioxide Capture.

Degree: PhD, Chemical Engineering, 2016, University of Toledo

URL: http://rave.ohiolink.edu/etdc/view?acc_num=toledo1474118357472385

► Concerns over the effects of anthropogenic carbon dioxide (CO2) emissions from fossil-fuel electric power plants has led to significant efforts in the development of processes… (more)

▼ Concerns over the effects of anthropogenic carbon dioxide (CO2) emissions from fossil-fuel electric power plants has led to significant efforts in the development of processes for CO2 capture from flue gas. Options under consideration include absorption, adsorption, membrane, and hybrid processes. The US Department of Energy (DOE) has set goals of 90% CO2 capture at 95% purity followed by compression to 140 bar for transport and storage. Ideally, the Levelized Cost of Electricity (LCOE) would increase by no more than 35%.Because of the relatively low CO2 concentration in post-combustion flue gas, most of the reported process configurations for membrane systems have sought to generate affordable CO2 partial pressure driving forces for permeation. Membrane Technology and Research, Inc. (MTR) proposed the use of an air feed sweep system to increase the CO2 concentration in flue gas. This process utilizes a two-stage membrane process in which the feed air to the furnace sweeps the flue gas in the second stage to reduce the flow of CO2 in the effluent to 10% of that leaving the furnace. Such a design significantly reduces capture costs but leads to a detrimental reduction in the oxygen concentration of the feed air to the boiler.In this dissertation, the economic viability of combined cryogenic-membrane separation is evaluated. The work incorporates the tradeoff between CO2/N2 selectivity and CO2 permeability that exists when considering the broad range of potential membrane materials. Of particular interest is the use of lower selectivity, higher permeability materials such as polydimethylsiloxane (PDMS). Additional enriching stages are required in a membrane-cryogenic air feed sweep configuration to enable use of these materials and achieve the 90% CO2 recovery and 95% purity targets. The higher CO2 permeance of PDMS significantly reduces the total module membrane area requirement and associated capital cost (CAPEX). However, the lower selectivity increases the parasitic plant load required to produce the desired CO2 purity due the need for an additional membrane stage and the associated recycle loops; this increases operating cost (OPEX). Multistage membrane-cryogenic air feed sweep configurations are optimized using the Robeson upper bound relation to relate membrane permeability to selectivity. Membrane selectivity is varied over a broad range encompassing the values considered by MTR. Permeability is varied with selectivity according to the variation anticipated by the upper bound of the Robeson plot for CO2 and N2. Membrane permeance is calculated assuming membranes can be fabricated with an effective thickness of 0.1 micron. Additionally, the two stages may utilize different membrane materials. The feed and permeate pressures also are varied over ranges encompassing the values proposed by MTR.The optimization space of membrane properties and operating conditions is scanned globally to determine the process design that minimizes LCOE. The oxygen concentration to the boiler is evaluated during the optimization… Advisors/Committee Members: LIPSCOMB, GLENN (Committee Chair).

Subjects/Keywords: Chemical Engineering; Hollow fiber membrane, Post-combustion carbon capture, carbon dioxide, membrane gas separations

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APA (6^th Edition):

CHE MAT, N. B. (2016). Membrane Process Design for Post-Combustion Carbon Dioxide Capture. (Doctoral Dissertation). University of Toledo. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=toledo1474118357472385

Chicago Manual of Style (16^th Edition):

CHE MAT, NORFAMILA BINTI. “Membrane Process Design for Post-Combustion Carbon Dioxide Capture.” 2016. Doctoral Dissertation, University of Toledo. Accessed April 15, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1474118357472385.

MLA Handbook (7^th Edition):

CHE MAT, NORFAMILA BINTI. “Membrane Process Design for Post-Combustion Carbon Dioxide Capture.” 2016. Web. 15 Apr 2021.

Vancouver:

CHE MAT NB. Membrane Process Design for Post-Combustion Carbon Dioxide Capture. [Internet] [Doctoral dissertation]. University of Toledo; 2016. [cited 2021 Apr 15]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=toledo1474118357472385.

Council of Science Editors:

CHE MAT NB. Membrane Process Design for Post-Combustion Carbon Dioxide Capture. [Doctoral Dissertation]. University of Toledo; 2016. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=toledo1474118357472385

University of Alabama

11. Horne, William Jeffrey. Understanding ionic liquid/poly(ionic liquid) properties at the molecular level to observe their effect on the transport of solutes.

Degree: 2015, University of Alabama

URL: http://purl.lib.ua.edu/127899

► The objective of this dissertation is to obtain a better understanding of how the molecular level properties of ionic liquids and poly(ionic liquids) effect the… (more)

Subjects/Keywords: Electronic Thesis or Dissertation; – thesis; Chemical engineering; absorption; COSMOTherm; gas separations; ionic liquids; poly(ionic liquids); polymers

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APA (6^th Edition):

Horne, W. J. (2015). Understanding ionic liquid/poly(ionic liquid) properties at the molecular level to observe their effect on the transport of solutes. (Thesis). University of Alabama. Retrieved from http://purl.lib.ua.edu/127899

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Horne, William Jeffrey. “Understanding ionic liquid/poly(ionic liquid) properties at the molecular level to observe their effect on the transport of solutes.” 2015. Thesis, University of Alabama. Accessed April 15, 2021. http://purl.lib.ua.edu/127899.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Horne, William Jeffrey. “Understanding ionic liquid/poly(ionic liquid) properties at the molecular level to observe their effect on the transport of solutes.” 2015. Web. 15 Apr 2021.

Vancouver:

Horne WJ. Understanding ionic liquid/poly(ionic liquid) properties at the molecular level to observe their effect on the transport of solutes. [Internet] [Thesis]. University of Alabama; 2015. [cited 2021 Apr 15]. Available from: http://purl.lib.ua.edu/127899.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Horne WJ. Understanding ionic liquid/poly(ionic liquid) properties at the molecular level to observe their effect on the transport of solutes. [Thesis]. University of Alabama; 2015. Available from: http://purl.lib.ua.edu/127899

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Waterloo

12. Francisco, Gil J. Separation of Carbon Dioxide from Nitrogen Using Poly(vinyl alcohol)-Amine Blend Membranes.

Degree: 2006, University of Waterloo

URL: http://hdl.handle.net/10012/2851

► Abstract In this research, a facilitated transport membrane was developed. The reactive membrane consisted of a carrier entrapped in poly(vinyl alcohol) "PVA" matrix cast on… (more)

▼ Abstract In this research, a facilitated transport membrane was developed. The reactive membrane consisted of a carrier entrapped in poly(vinyl alcohol) "PVA" matrix cast on a polysulfone support. PVA was selected to hold the reactive carrier because of its hydrophilicity and compatibility with the carrier. Several reactive amines were examined for their suitability as carrier. Among the amines tested as a carrier for CO₂, diethanolamine "DEA" demonstrates a greater improvement in the permeation of CO₂ as well as selectivity over N₂. DEA is a secondary amine and one of the most commonly used amines for gas treating due to its favourable reaction kinetics with acid gases and because of its stability when regenerated. Initially, pure gas permeation was employed for materials selection and membrane preparation procedures. The effects of process conditions on the membrane performance, which involve carrier concentrations, feed pressures and operating temperatures were examined. Then the effects of membrane thickness and long-term stability tests were conducted. Once the appropriate membrane materials and preparation procedures were established, the next phase of the study involved the determination of the actual separation of CO₂/N₂ mixtures. These experiments were carried out by adjusting the feed gas composition, feed pressures and operating temperature. In general, the results obtained with CO₂/N₂ mixtures were in agreement with those obtained with pure gas permeation experiments. It was found that facilitation is more significant at lower CO₂ partial pressure differential across the membrane. At higher partial pressure differentials, the reactive membrane may no longer serve as a facilitating medium due to the saturation of the reactive part of the membrane. Under such conditions the permeance values and selectivity obtained were simply due to the solubility and diffusivity of the CO₂ and N₂ in the membrane matrix. Since it was not possible to analyze concentration profiles inside the thin membrane experimentally, it was decided to analyze the effects of various parameters through the analytical transport equations. The zwitterion mechanism was used to illustrate the kinetics of the CO₂-DEA systems. The mass transport equations were solved numerically. All relevant physicochemical properties needed to implement the mass transport equations were taken from the literatures. The calculated results support the experimental trends that were observed for the CO₂ permeance as a function of partial pressure differentials and carrier concentrations.

Subjects/Keywords: Chemical Engineering; Facilitated transport; Gas separations; membranes

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APA (6^th Edition):

Francisco, G. J. (2006). Separation of Carbon Dioxide from Nitrogen Using Poly(vinyl alcohol)-Amine Blend Membranes. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/2851

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Francisco, Gil J. “Separation of Carbon Dioxide from Nitrogen Using Poly(vinyl alcohol)-Amine Blend Membranes.” 2006. Thesis, University of Waterloo. Accessed April 15, 2021. http://hdl.handle.net/10012/2851.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Francisco, Gil J. “Separation of Carbon Dioxide from Nitrogen Using Poly(vinyl alcohol)-Amine Blend Membranes.” 2006. Web. 15 Apr 2021.

Vancouver:

Francisco GJ. Separation of Carbon Dioxide from Nitrogen Using Poly(vinyl alcohol)-Amine Blend Membranes. [Internet] [Thesis]. University of Waterloo; 2006. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/10012/2851.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Francisco GJ. Separation of Carbon Dioxide from Nitrogen Using Poly(vinyl alcohol)-Amine Blend Membranes. [Thesis]. University of Waterloo; 2006. Available from: http://hdl.handle.net/10012/2851

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Berkeley

13. Ellison, Paul Andrew. I. Nuclear Production Reaction and Chemical Isolation Procedure for 240Am II. New Superheavy Element Isotopes: 242Pu(48Ca,5n)285-114.

Degree: Chemistry, 2011, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/9p27t1p5

► Part I discusses the study of a new nuclear reaction and chemical separation procedure for the production of ²⁴⁰Am. Thin ²⁴²Pu, ^natTi, and ^natNi targets… (more)

Subjects/Keywords: Nuclear chemistry; Physical chemistry; Nuclear physics; americium-240; Berkeley Gas-filled Separator; element 114; separations; superheavy elements; transactinides

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APA (6^th Edition):

Ellison, P. A. (2011). I. Nuclear Production Reaction and Chemical Isolation Procedure for 240Am II. New Superheavy Element Isotopes: 242Pu(48Ca,5n)285-114. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/9p27t1p5

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ellison, Paul Andrew. “I. Nuclear Production Reaction and Chemical Isolation Procedure for 240Am II. New Superheavy Element Isotopes: 242Pu(48Ca,5n)285-114.” 2011. Thesis, University of California – Berkeley. Accessed April 15, 2021. http://www.escholarship.org/uc/item/9p27t1p5.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ellison, Paul Andrew. “I. Nuclear Production Reaction and Chemical Isolation Procedure for 240Am II. New Superheavy Element Isotopes: 242Pu(48Ca,5n)285-114.” 2011. Web. 15 Apr 2021.

Vancouver:

Ellison PA. I. Nuclear Production Reaction and Chemical Isolation Procedure for 240Am II. New Superheavy Element Isotopes: 242Pu(48Ca,5n)285-114. [Internet] [Thesis]. University of California – Berkeley; 2011. [cited 2021 Apr 15]. Available from: http://www.escholarship.org/uc/item/9p27t1p5.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ellison PA. I. Nuclear Production Reaction and Chemical Isolation Procedure for 240Am II. New Superheavy Element Isotopes: 242Pu(48Ca,5n)285-114. [Thesis]. University of California – Berkeley; 2011. Available from: http://www.escholarship.org/uc/item/9p27t1p5

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Washington State University

14. [No author]. Influence of Multivalent Metal Cations on Carbohydrate Separations and Fragmentation Patterns via Ion Mobility-Mass Spectrometry .

Degree: 2019, Washington State University

URL: http://hdl.handle.net/2376/16782

► Carbohydrates, oligosaccharides, and glycans occupy a corner of biopolymers that can be overlooked in the shadow of proteins and nucleic acids but are nonetheless essential… (more)

▼ Carbohydrates, oligosaccharides, and glycans occupy a corner of biopolymers that can be overlooked in the shadow of proteins and nucleic acids but are nonetheless essential for the survival of biological organisms. However, unlike other biological macromolecules, known carbohydrate units have largely homogeneous elemental compositions, where species are instead distinguished by variations in stereochemistry and branching patterns. Because this creates a scenario where complex biological samples may contain isomeric mixtures which cannot be differentiated by mass isolation, incorporating ion mobility separations in front of mass spectrometry can provide another dimension of information to distinguish among isomers. Yet another angle for enhancing glycan analysis with ion mobility-mass spectrometry is by leveraging interactions between carbohydrate species and metal cations, which can form adducts that have altered gas-phase structures relative to protonated or deprotonated ions. In some situations, metal adduction exaggerates the differences in effective size among isomers and thereby facilitates isomeric glycan separation in the drift time space. This dissertation is focused on conveying the utility of metal-glycan interactions for improving the ion mobility-mass spectrometric analysis of carbohydrate species while also describing some complementary experiments that were pursued in support of glycan analysis. Of note, ultraviolet photodissociation (UVPD) with metal-enhanced fragmentation and Fourier multiplexing of ion mobility-ion trap mass spectrometry contributed well to isomeric mixture analysis. Divalent metal cations including select transition metals and alkaline earth metals were evaluated for their potential to enhance drift time separations, with transition metals proving particularly useful in this regard for mixture analysis. Preliminary oligosaccharide analysis with divalent metal species found that carbohydrates will form both singly-charged monomeric metal-glycan adducts as well as doubly-charged dimeric metal-glycan adducts where both appear at the same m/z value. These dimers were subsequently scrutinized for the potential to form heterodimeric metal-glycan dimers wherein two different isomeric glycans could form a single dimer during a mixture analysis without mobility separation and form chimeric mass spectra. Through a combination of isotopic labeling and ion mobility-mass spectrometry, it was shown that heterodimeric metal-glycan species will form, and that mobility separation is vital for analyzing glycan mixtures. Advisors/Committee Members: Clowers, Brian H (advisor).

Subjects/Keywords: Analytical chemistry; Fourier transform; Gas-phase separations; Ion mobility spectrometry; Metal-glycan complexes; Tandem mass spectrometry; Ultraviolet photodissociation

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APA (6^th Edition):

author], [. (2019). Influence of Multivalent Metal Cations on Carbohydrate Separations and Fragmentation Patterns via Ion Mobility-Mass Spectrometry . (Thesis). Washington State University. Retrieved from http://hdl.handle.net/2376/16782

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

author], [No. “Influence of Multivalent Metal Cations on Carbohydrate Separations and Fragmentation Patterns via Ion Mobility-Mass Spectrometry .” 2019. Thesis, Washington State University. Accessed April 15, 2021. http://hdl.handle.net/2376/16782.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

author], [No. “Influence of Multivalent Metal Cations on Carbohydrate Separations and Fragmentation Patterns via Ion Mobility-Mass Spectrometry .” 2019. Web. 15 Apr 2021.

Vancouver:

author] [. Influence of Multivalent Metal Cations on Carbohydrate Separations and Fragmentation Patterns via Ion Mobility-Mass Spectrometry . [Internet] [Thesis]. Washington State University; 2019. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/2376/16782.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

author] [. Influence of Multivalent Metal Cations on Carbohydrate Separations and Fragmentation Patterns via Ion Mobility-Mass Spectrometry . [Thesis]. Washington State University; 2019. Available from: http://hdl.handle.net/2376/16782

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

15. Wiersum, Andrew. Developing a strategy to evaluate the potential of new porous materials for the separation of gases by adsorption : Elaboration d'une stratégie pour évaluer le potentiel de nouveaux matériaux poreux pour la séparation des gaz par adsorption.

Degree: Docteur es, Sciences des Matériaux, Physique, Chimie et Nanosciences, 2012, Aix Marseille Université

URL: http://www.theses.fr/2012AIXM4817

►

Les Metal-Organic Framework (MOF) sont des adsorbants très prometteurs pour la séparation des gaz. Formés de centres métalliques reliés par des ligands organiques, ces matériaux… (more)

▼

Les Metal-Organic Framework (MOF) sont des adsorbants très prometteurs pour la séparation des gaz. Formés de centres métalliques reliés par des ligands organiques, ces matériaux présentent une structure organisée avec des pores de taille contrôlée ainsi que des surfaces et des volumes poreux très élevées. La possibilité de faire varier à la fois le centre métallique et le ligand organique donne aux MOFs une très grande diversité qu'on ne retrouve pas chez les zéolithes et les charbons actifs.L'objectif de cette étude a été d'évaluer le potentiel des MOFs en tant qu'adsorbants pour quatre procédés de séparation de gaz. En raison du grand nombre de MOFs disponibles, il a été nécessaire d'élaborer une stratégie pour identifier les matériaux les plus prometteurs dans chaque cas. Cette méthodologie comprend quatre étapes : une étape de criblage, une étape expérimentale, une étape de calcul et une étape d'évaluation.Pour l'étape de criblage, un nouvel appareil dit « à haut débit » a été développé pour mesurer des isothermes approximatives. Ensuite, un certain nombre de matériaux ont été retenus pour faire une étude plus approfondie de leurs propriétés d'adsorption. Des isothermes très précises ont été mesurées par gravimétrie tandis que les enthalpies d'adsorption ont été obtenues par microcalorimétrie. Dans l'étape de calcul, le modèle IAST a été utilisée pour prédire les sélectivités à partir des données en gaz pur. Enfin, les adsorbants ont été classés à l'aide d'un nouveau paramètre de sélection qui regroupe la sélectivité, la capacité efficace et l'enthalpie d'adsorption, où l'importance de chacun des paramètres peut être ajustée en fonction des besoins du procédé.

Metal-Organic Frameworks (MOFs) are seen to be one of the most promising classes of adsorbents for gas separations. Consisting of metal clusters connected by organic linkers to form a fully crystalline network, these materials have record breaking surface areas and pore volumes as well as a wide variety of pore structures and sizes. This, coupled with the possibility to use virtually any transition metal as well as functionalized linkers, gives MOFs the chemical and physical versatility often lacking in traditional adsorbents such as zeolites and activated carbons.The purpose of this study was to evaluate the potential of MOFs as adsorbents for four gas separations of interest to the petrochemical industry. Because of the diversity and number of MOFs available, a methodology was needed to help identify the most promising materials in each case. The proposed methodology comprises four stages: a screening step, an experimental step, a computational step and finally an evaluation step. For the first stage, a high-throughput setup was developed to measure rough adsorption isotherms. A number of materials were then selected for a more thorough investigation of their adsorption properties. Highly accurate isotherms were measured gravimetrically while precise adsorption enthalpies were obtained by microcalorimetry. Step three involved predicting the…

Advisors/Committee Members: Llewellyn, Philip (thesis director).

Subjects/Keywords: Metal-Organic Frameworks; Adsorption; Séparation de gaz; Microcalorimétrie; Criblage; Metal-Organic Frameworks; Adsorption; Gas separations; Microcalorimetry; Screening

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wiersum, A. (2012). Developing a strategy to evaluate the potential of new porous materials for the separation of gases by adsorption : Elaboration d'une stratégie pour évaluer le potentiel de nouveaux matériaux poreux pour la séparation des gaz par adsorption. (Doctoral Dissertation). Aix Marseille Université. Retrieved from http://www.theses.fr/2012AIXM4817

Chicago Manual of Style (16^th Edition):

Wiersum, Andrew. “Developing a strategy to evaluate the potential of new porous materials for the separation of gases by adsorption : Elaboration d'une stratégie pour évaluer le potentiel de nouveaux matériaux poreux pour la séparation des gaz par adsorption.” 2012. Doctoral Dissertation, Aix Marseille Université. Accessed April 15, 2021. http://www.theses.fr/2012AIXM4817.

MLA Handbook (7^th Edition):

Wiersum, Andrew. “Developing a strategy to evaluate the potential of new porous materials for the separation of gases by adsorption : Elaboration d'une stratégie pour évaluer le potentiel de nouveaux matériaux poreux pour la séparation des gaz par adsorption.” 2012. Web. 15 Apr 2021.

Vancouver:

Wiersum A. Developing a strategy to evaluate the potential of new porous materials for the separation of gases by adsorption : Elaboration d'une stratégie pour évaluer le potentiel de nouveaux matériaux poreux pour la séparation des gaz par adsorption. [Internet] [Doctoral dissertation]. Aix Marseille Université 2012. [cited 2021 Apr 15]. Available from: http://www.theses.fr/2012AIXM4817.

Council of Science Editors:

Wiersum A. Developing a strategy to evaluate the potential of new porous materials for the separation of gases by adsorption : Elaboration d'une stratégie pour évaluer le potentiel de nouveaux matériaux poreux pour la séparation des gaz par adsorption. [Doctoral Dissertation]. Aix Marseille Université 2012. Available from: http://www.theses.fr/2012AIXM4817

University of Colorado

16. McDanel, William Michael. Design and Development of Room Temperature Ionic Liquid-Based Epoxy-Amine Resins and Ion Gels for Membrane-Based CO2 Separations.

Degree: PhD, Chemical & Biochemical Engineering, 2015, University of Colorado

URL: https://scholar.colorado.edu/chbe_gradetds/76

► Room temperature ionic liquids (RTILs) have very attractive CO₂ permeabilities and CO₂/light gas permeability selectivities as supported membranes. However, RTILs are displaced as supported… (more)

Subjects/Keywords: Epoxy resins; Facilitated tansport; Ion gels; Membrane gas separations; Room temperature ionic liquids; Polymer Chemistry; Polymer Science

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APA (6^th Edition):

McDanel, W. M. (2015). Design and Development of Room Temperature Ionic Liquid-Based Epoxy-Amine Resins and Ion Gels for Membrane-Based CO2 Separations. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/chbe_gradetds/76

Chicago Manual of Style (16^th Edition):

McDanel, William Michael. “Design and Development of Room Temperature Ionic Liquid-Based Epoxy-Amine Resins and Ion Gels for Membrane-Based CO2 Separations.” 2015. Doctoral Dissertation, University of Colorado. Accessed April 15, 2021. https://scholar.colorado.edu/chbe_gradetds/76.

MLA Handbook (7^th Edition):

McDanel, William Michael. “Design and Development of Room Temperature Ionic Liquid-Based Epoxy-Amine Resins and Ion Gels for Membrane-Based CO2 Separations.” 2015. Web. 15 Apr 2021.

Vancouver:

McDanel WM. Design and Development of Room Temperature Ionic Liquid-Based Epoxy-Amine Resins and Ion Gels for Membrane-Based CO2 Separations. [Internet] [Doctoral dissertation]. University of Colorado; 2015. [cited 2021 Apr 15]. Available from: https://scholar.colorado.edu/chbe_gradetds/76.

Council of Science Editors:

McDanel WM. Design and Development of Room Temperature Ionic Liquid-Based Epoxy-Amine Resins and Ion Gels for Membrane-Based CO2 Separations. [Doctoral Dissertation]. University of Colorado; 2015. Available from: https://scholar.colorado.edu/chbe_gradetds/76

17. Carter, David. Fabrication and Characterization of Silicalite-1 Membranes for the Separation of the Greenhouse Gases .

Degree: 2019, University of Ottawa

URL: http://hdl.handle.net/10393/39524

► Membranes composed of zeolite crystals, in which gas molecules are transported by surface diffusion, are promising for gas separation applications. Since this mode of mass… (more)

▼ Membranes composed of zeolite crystals, in which gas molecules are transported by surface diffusion, are promising for gas separation applications. Since this mode of mass transfer mechanism is controlled by synergistic adsorption and diffusion phenomena, the separation of gas mixtures is not solely dependent on molecular size. However, undesirable defect pathways in zeolite membranes are often present due to factors such as incomplete crystal growth and/or thermal stresses during membrane synthesis and calcination. These pathways cause molecules to bypass the selective zeolite crystal layer and adversely affect membrane performance. Since the fabrication of defect-free zeolite membranes is very challenging, their widespread adoption for industrial processes has been impeded. Quantification of defects in zeolite membranes is therefore important to improve synthesis protocols of these membranes. In this research, zeolite membranes composed of silicalite crystals have been fabricated using the pore plugging method, and their performance was evaluated by developing a method that can be used to describe the selective and non-selective channels that are present in any zeolite membrane. Unlike the other destructive and sophisticated methods, which already exist to discern this information, the proposed method requires only a limited number of in-situ permeation experiments to be conducted using He – a non-adsorbing gas, and N2 – an adsorbing gas. With this method, the volume fraction, effective length, and size of the selective and non-selective channels of multiple membranes have been quantified, and these parameters were used to predict membrane performance at untested conditions, as well as with untested gases such as CH4 and CO2. In addition, by separating surface diffusion from the flow through the defects in gas separation tests with CO2/N2 mixture, the respective transport diffusivities and exchange diffusivity coefficients, which account for mass transfer in zeolite crystals were determined using the Maxwell-Stefan model. These determined exchange diffusivity coefficients are not equal to each other and challenge the Vignes correlation. In addition, transport diffusivities determined in mixed gas permeation experiments at University of Ottawa have then been validated by large single crystal transport diffusivities for mixed gases that were determined from molecular uptake experiments conducted at University of Leipzig in Germany, using Infra-Red Micro-imaging.

Subjects/Keywords: Inorganic Membranes; Silicalite; Adsorption; Diffusion; Gas Separations

…Single Gas Permeances for He, N2, CH4, and CO2 20 2.4.3 Effective Diffusivities for N2, CH4… …Morphological and Compositional Analysis 43 43 3.3.2 Silicalite-1 Single Gas Adsorption Isotherms… …and Diffusion Kinetics 47 3.3.3 Single Gas Membrane Permeation 51 3.3.4 Mixture Gas… …Procedure 101 ix 5.3.2 Gas Permeation Experiments 102 5.3.3 Parameters for the Proposed… …Method 104 5.4.0 RESULTS AND DISCUSSION 105 5.4.1 Experimental Pure Gas Permeances 105…

14 more images…

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APA (6^th Edition):

Carter, D. (2019). Fabrication and Characterization of Silicalite-1 Membranes for the Separation of the Greenhouse Gases . (Thesis). University of Ottawa. Retrieved from http://hdl.handle.net/10393/39524

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Carter, David. “Fabrication and Characterization of Silicalite-1 Membranes for the Separation of the Greenhouse Gases .” 2019. Thesis, University of Ottawa. Accessed April 15, 2021. http://hdl.handle.net/10393/39524.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Carter, David. “Fabrication and Characterization of Silicalite-1 Membranes for the Separation of the Greenhouse Gases .” 2019. Web. 15 Apr 2021.

Vancouver:

Carter D. Fabrication and Characterization of Silicalite-1 Membranes for the Separation of the Greenhouse Gases . [Internet] [Thesis]. University of Ottawa; 2019. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/10393/39524.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Carter D. Fabrication and Characterization of Silicalite-1 Membranes for the Separation of the Greenhouse Gases . [Thesis]. University of Ottawa; 2019. Available from: http://hdl.handle.net/10393/39524

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Notre Dame

18. Jennifer Lynn Anthony. Gas Solubilities in Ionic Liquids: Experimental Measurements and Applications</h1>.

Degree: Chemical and Biomolecular Engineering, 2004, University of Notre Dame

URL: https://curate.nd.edu/show/w9504x54118

► Solvents play an extremely important role in many industrial processes, acting as a media for chemical reactions or for extraction of products. Typically, these… (more)

▼ Solvents play an extremely important role in many industrial processes, acting as a media for chemical reactions or for extraction of products. Typically, these solvents are volatile organic compounds or VOCs. As the VOCs volatilize, the risk of human exposure through inhalation is increased. VOCs have also been found to increase ozone depletion and smog formation. Therefore, it is important to find other solvents that still meet the needs of industry while limiting the environmental and health risks. Room temperature ionic liquids (ILs) have recently been getting attention as potential environmentally benign or “green" solvents. Ionic liquids, organic salts that are liquids in their pure states at ambient conditions, have many properties that are similar to conventional organic solvents. But, many ILs also have the unique characteristic in that they exhibit a vanishingly low vapor pressure. This negligible volatility eliminates many of the concerns associated with traditional organic solvents by decreasing the risk of worker exposure and the loss of solvent to the atmosphere. The main objective of this research is to determine thermodynamic/phase behavior properties by studying the phase behavior of the ionic liquids with various gases and liquids to further develop the relationships between these properties and the molecular structure of these ionic liquids. Knowledge of these properties is necessary prior to design and development of industrially relevant processes using ILs. This work explores the solubility and associated thermodynamic properties, such as Henry’s law constants, and enthalpies and entropies of absorption, of a variety of gases in various ionic liquids, mainly those with 1-n-butyl-3-methylimidazolium as the cation and [PF6], [BF4], and [Tf2N] as the anions. The gases considered range from simple nonpolar compounds to more complex polar gases capable of hydrogen bonding. Water vapor, carbon dioxide, and nitrous oxide show the strongest interactions with the ionic liquids, whereas gases like N2, O2 and Ar are only sparingly soluble. This work also shows ionic liquids have potential for use as a gas separation medium. Advisors/Committee Members: Professor John Uhran, Committee Member, Professor Mark Stadtherr, Committee Member, Professor Eduardo Wolf, Committee Member, Professor William Strieder, Committee Member, Professor Joan Brennecke, Committee Co-Chair, Professor Edward Maginn, Committee Co-Chair.

Subjects/Keywords: Henry’s constants; separations; carbon dioxide; gas solubilities; ionic liquids

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APA (6^th Edition):

Anthony, J. L. (2004). Gas Solubilities in Ionic Liquids: Experimental Measurements and Applications</h1>. (Thesis). University of Notre Dame. Retrieved from https://curate.nd.edu/show/w9504x54118

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Anthony, Jennifer Lynn. “Gas Solubilities in Ionic Liquids: Experimental Measurements and Applications</h1>.” 2004. Thesis, University of Notre Dame. Accessed April 15, 2021. https://curate.nd.edu/show/w9504x54118.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Anthony, Jennifer Lynn. “Gas Solubilities in Ionic Liquids: Experimental Measurements and Applications</h1>.” 2004. Web. 15 Apr 2021.

Vancouver:

Anthony JL. Gas Solubilities in Ionic Liquids: Experimental Measurements and Applications</h1>. [Internet] [Thesis]. University of Notre Dame; 2004. [cited 2021 Apr 15]. Available from: https://curate.nd.edu/show/w9504x54118.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Anthony JL. Gas Solubilities in Ionic Liquids: Experimental Measurements and Applications</h1>. [Thesis]. University of Notre Dame; 2004. Available from: https://curate.nd.edu/show/w9504x54118

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

19. Wenz, Graham Benjamin. Tuning carbon molecular sieve membrane performance for challenging gas separations.

Degree: PhD, Chemical and Biomolecular Engineering, 2017, Georgia Tech

URL: http://hdl.handle.net/1853/59785

► Membranes are emerging as tools for energy efficient alternatives to thermally-driven phase-changed based gas separations. As direct replacement of traditional separation processes with membrane-based processes… (more)

Subjects/Keywords: Membranes; Gas separations; Carbon molecular sieves

…transformational tools for large-scale industrial gas separations. Their simplicity and potential to… …challenging gas separations. xxi CHAPTER 1. 1.1 INTRODUCTION Energy Production: Advancements… …separations for natural gas treatment, or upgrading, is typically performed via solvent-based… …scale gas separations. Due to the prevalence of traditional phasechange thermally-driven… …growing field for energy-efficient large-scale gas separations. While direct replacement of…

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APA (6^th Edition):

Wenz, G. B. (2017). Tuning carbon molecular sieve membrane performance for challenging gas separations. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/59785

Chicago Manual of Style (16^th Edition):

Wenz, Graham Benjamin. “Tuning carbon molecular sieve membrane performance for challenging gas separations.” 2017. Doctoral Dissertation, Georgia Tech. Accessed April 15, 2021. http://hdl.handle.net/1853/59785.

MLA Handbook (7^th Edition):

Wenz, Graham Benjamin. “Tuning carbon molecular sieve membrane performance for challenging gas separations.” 2017. Web. 15 Apr 2021.

Vancouver:

Wenz GB. Tuning carbon molecular sieve membrane performance for challenging gas separations. [Internet] [Doctoral dissertation]. Georgia Tech; 2017. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/1853/59785.

Council of Science Editors:

Wenz GB. Tuning carbon molecular sieve membrane performance for challenging gas separations. [Doctoral Dissertation]. Georgia Tech; 2017. Available from: http://hdl.handle.net/1853/59785

Virginia Tech

20. Vaughan, Benjamin Ray. Polymer Aluminophosphate Mixed Matrix Membranes for Gas Separations.

Degree: PhD, Chemical Engineering, 2007, Virginia Tech

URL: http://hdl.handle.net/10919/26908

► It is well known that clays dispersed in a polymer matrix decrease the permeability of all gases through that membrane. Our objective was to explore… (more)

▼ It is well known that clays dispersed in a 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 size range of 3-4 Ã . The molecular level dispersion of this material into a polymer matrix is theorized to increase selectivity by molecular sieving. A previous study performed in our laboratory showed an increase in He/CH4 selectivity when this aluminophosphate (8MR-AlPO) was dispersed in a fluorinated polyimide. The increase in selectivity was explained as size sieving by the aluminophosphate sheets where small gas species can pass through the microstructure and large gas species have to take a tortuous path around the sheets. We performed several studies with different polymer materials in the attempt to make composite membranes that corroborated the previously seen increases in gas selectivity. In some cases different surfactants were used to swell 8MR-AlPO. In the first set of studies the methods used to produce the fluorinated polyimide composites were repeated using polydimethyl siloxane (PDMS), a copolymer of a fluorinated polyimide and PDMS, polysulfone, Matrimid, and cellulose acetate as the matrix materials. In general gas permeation studies of these materials showed an overall decrease in permeability with increasing addition of 8MR-AlPO but no substantial increase in selectivity. In an attempt to increase the chances of exfoliating and dispersing the layered aluminophosphate, an in-situ method using poly(etherimide) (PEI) was polymerized in the presence of 8MR-AlPO was employed. Mixed matrix membranes of PEI with 5wt% 8MR-AlPO were successfully fabricated and the transport properties measured. Microscopy revealed that the composites made with the 8MR-AlPO treated with a reactive surfactant showed better dispersion than those treated with the nonreactive surfactants. The permeability of gases changed very little as the result of adding 8MR-AlPO to PEI and no substantial increase in selectivity was observed. Finally, we incorporated a similar layered aluminophosphate with larger 12MR (6-7Ã ) openings into polysulfone. These composites showed barrier behavior but no increases in selectivity. Advisors/Committee Members: Marand, Eva (committeechair), Koros, William (committee member), Davis, Richey M. (committee member), Oyama, Shigeo Ted (committee member).

Subjects/Keywords: layered aluminophosphates; mixed matrix membranes; gas separations

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APA (6^th Edition):

Vaughan, B. R. (2007). Polymer Aluminophosphate Mixed Matrix Membranes for Gas Separations. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/26908

Chicago Manual of Style (16^th Edition):

Vaughan, Benjamin Ray. “Polymer Aluminophosphate Mixed Matrix Membranes for Gas Separations.” 2007. Doctoral Dissertation, Virginia Tech. Accessed April 15, 2021. http://hdl.handle.net/10919/26908.

MLA Handbook (7^th Edition):

Vaughan, Benjamin Ray. “Polymer Aluminophosphate Mixed Matrix Membranes for Gas Separations.” 2007. Web. 15 Apr 2021.

Vancouver:

Vaughan BR. Polymer Aluminophosphate Mixed Matrix Membranes for Gas Separations. [Internet] [Doctoral dissertation]. Virginia Tech; 2007. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/10919/26908.

Council of Science Editors:

Vaughan BR. Polymer Aluminophosphate Mixed Matrix Membranes for Gas Separations. [Doctoral Dissertation]. Virginia Tech; 2007. Available from: http://hdl.handle.net/10919/26908

Virginia Tech

21. Krych, Wojtek S. Fabrication and Gas Permeation Studies on Polyimide/Layered-Aluminum Phosphate Nanocomposite Membranes.

Degree: MS, Chemical Engineering, 2003, Virginia Tech

URL: http://hdl.handle.net/10919/43525

► Polymer â clay nanocomposites have improved thermal, mechanical, and barrier properties when compared with the pure polymer. The objective of this study was to examine… (more)

Subjects/Keywords: Gas Separations; Nanocomposite Materials; Polyimide; Aluminum Phosphate

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APA (6^th Edition):

Krych, W. S. (2003). Fabrication and Gas Permeation Studies on Polyimide/Layered-Aluminum Phosphate Nanocomposite Membranes. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/43525

Chicago Manual of Style (16^th Edition):

Krych, Wojtek S. “Fabrication and Gas Permeation Studies on Polyimide/Layered-Aluminum Phosphate Nanocomposite Membranes.” 2003. Masters Thesis, Virginia Tech. Accessed April 15, 2021. http://hdl.handle.net/10919/43525.

MLA Handbook (7^th Edition):

Krych, Wojtek S. “Fabrication and Gas Permeation Studies on Polyimide/Layered-Aluminum Phosphate Nanocomposite Membranes.” 2003. Web. 15 Apr 2021.

Vancouver:

Krych WS. Fabrication and Gas Permeation Studies on Polyimide/Layered-Aluminum Phosphate Nanocomposite Membranes. [Internet] [Masters thesis]. Virginia Tech; 2003. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/10919/43525.

Council of Science Editors:

Krych WS. Fabrication and Gas Permeation Studies on Polyimide/Layered-Aluminum Phosphate Nanocomposite Membranes. [Masters Thesis]. Virginia Tech; 2003. Available from: http://hdl.handle.net/10919/43525

Colorado School of Mines

22. Evans, Tabitha J. Utilization of metal-organic frameworks for gas separations and catalytic oxidation.

Degree: MS(M.S.), Chemistry, 2018, Colorado School of Mines

URL: http://hdl.handle.net/11124/172835

► Metal-organic frameworks (MOFs) and their applications have been a rapidly growing area of research in recent years. The seemingly endless combinations of metal ions or… (more)

▼ Metal-organic frameworks (MOFs) and their applications have been a rapidly growing area of research in recent years. The seemingly endless combinations of metal ions or clusters with various possible organic linkers, along with the methods of post-synthesis modification, has resulted in approximately 20,000 different MOFs to date. With such potential for variation, MOFs have shown to be useful in a whole host of applications. One such application of MOFs is the separation of natural gas. Currently, these separations require expensive methods, such as amine absorptions and cryogenic distillation. Polymers, such as polyimide, have been investigated, but the necessary high temperatures lead to plasticization and poor separation performance. Alternatively, ZIF-8 (zeolitic imidazolate framework 8), a member of the ZIF class of MOFs, is a viable option due to its inherent pore size and preferential adsorption of carbon dioxide. Microporous carbon membranes have shown increased chemical and thermal stability. By converting the microporous ZIF-8 to a carbon membrane, the resulting membrane can be expected to maintain the separation properties of the parent ZIF-8 while gaining additional stability provided by carbon. Unfortunately, synthesizing this material is a challenge to reproduce due to the wide variety of methods for ZIF-8 synthesis and the limited study of the effect of carbonization on the parent material A second application of MOFs is as heterogeneous catalysts. Cu-BTC, or HKUST-1, is used for the oxidation of benzyl alcohol to benzaldehyde, a chemical commonly used in perfumery and pharmaceuticals. However, the use of copper requires the presence of TEMPO (2,2,6,6-tetramethylpiperidine-N-oxyl) as it is needed to deprotonate the alcohol. Unfortunately, TEMPO can interrupt the framework structure of Cu-BTC and poisons the catalysts. In order to help combat this problem, layer by layer synthesis of Cu-BTC was used to incorporate the MOF into the pores of a functionalized mesoporous silica nanoparticle (MSN). However, this incorporation did not protect the Cu-BTC, as the pores size of the protective MSN was insufficient to prevent TEMPO access. Additionally, only a small amount of Cu-BTC was synthesized within the pores, which magnified the effects of TEMPO poisoning. Advisors/Committee Members: Trewyn, Brian (advisor), Carreon, Moises A. (committee member), Richards, Ryan (committee member), Pylypenko, Svitlana (committee member).

Subjects/Keywords: Cu-BTC; mesoporous silica nanoparticles; natural gas separations; aerobic oxidation; metal-organic frameworks; HKURST-1; ZIF

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APA (6^th Edition):

Evans, T. J. (2018). Utilization of metal-organic frameworks for gas separations and catalytic oxidation. (Masters Thesis). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/172835

Chicago Manual of Style (16^th Edition):

Evans, Tabitha J. “Utilization of metal-organic frameworks for gas separations and catalytic oxidation.” 2018. Masters Thesis, Colorado School of Mines. Accessed April 15, 2021. http://hdl.handle.net/11124/172835.

MLA Handbook (7^th Edition):

Evans, Tabitha J. “Utilization of metal-organic frameworks for gas separations and catalytic oxidation.” 2018. Web. 15 Apr 2021.

Vancouver:

Evans TJ. Utilization of metal-organic frameworks for gas separations and catalytic oxidation. [Internet] [Masters thesis]. Colorado School of Mines; 2018. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/11124/172835.

Council of Science Editors:

Evans TJ. Utilization of metal-organic frameworks for gas separations and catalytic oxidation. [Masters Thesis]. Colorado School of Mines; 2018. Available from: http://hdl.handle.net/11124/172835

University of Minnesota

23. Phillip, William A. Block polymer membranes for selective separations.

Degree: PhD, Chemical Engineering, 2009, University of Minnesota

URL: http://purl.umn.edu/54649

► Polymeric membranes are used for many separations. Some act as selective filters, separating viruses and other undesirable solutes from drinking water. Others perform chemical separations,… (more)

Subjects/Keywords: Block Polymers; Filtration; Gas Diffusion; Gas Separations; Liquid Flow; Membranes; Chemical Engineering

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APA (6^th Edition):

Phillip, W. A. (2009). Block polymer membranes for selective separations. (Doctoral Dissertation). University of Minnesota. Retrieved from http://purl.umn.edu/54649

Chicago Manual of Style (16^th Edition):

Phillip, William A. “Block polymer membranes for selective separations.” 2009. Doctoral Dissertation, University of Minnesota. Accessed April 15, 2021. http://purl.umn.edu/54649.

MLA Handbook (7^th Edition):

Phillip, William A. “Block polymer membranes for selective separations.” 2009. Web. 15 Apr 2021.

Vancouver:

Phillip WA. Block polymer membranes for selective separations. [Internet] [Doctoral dissertation]. University of Minnesota; 2009. [cited 2021 Apr 15]. Available from: http://purl.umn.edu/54649.

Council of Science Editors:

Phillip WA. Block polymer membranes for selective separations. [Doctoral Dissertation]. University of Minnesota; 2009. Available from: http://purl.umn.edu/54649

24. Kemmerlin, Ruben Kyle. Carbon molecular sieve membranes for aggressive sour gas separations.

Degree: MS, Chemical Engineering, 2012, Georgia Tech

URL: http://hdl.handle.net/1853/50135

► It had been shown that the transport properties of CMS membranes varies as a function of H₂S exposure making the conditioning protocol an important step… (more)

Subjects/Keywords: CMS; Membrane separations; Acid gas; Sour gas; Molecular sieves; Gas separation membranes; Natural gas

…sour gas separations continued until the membrane was effectively “shut down” or if the… …x5B;6] Kiyono M. Carbon molecular sieve membranes for natural gas separations. Atlanta… …investigated natural gas separations using various polyimide precursors. Vu showed that under… …molecular sieve membranes for natural gas separations. Atlanta GA USA, Georgia Institute of… …Technology, 2010. [5] Steel KM. Carbon membranes for challenging gas separations…

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APA (6^th Edition):

Kemmerlin, R. K. (2012). Carbon molecular sieve membranes for aggressive sour gas separations. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/50135

Chicago Manual of Style (16^th Edition):

Kemmerlin, Ruben Kyle. “Carbon molecular sieve membranes for aggressive sour gas separations.” 2012. Masters Thesis, Georgia Tech. Accessed April 15, 2021. http://hdl.handle.net/1853/50135.

MLA Handbook (7^th Edition):

Kemmerlin, Ruben Kyle. “Carbon molecular sieve membranes for aggressive sour gas separations.” 2012. Web. 15 Apr 2021.

Vancouver:

Kemmerlin RK. Carbon molecular sieve membranes for aggressive sour gas separations. [Internet] [Masters thesis]. Georgia Tech; 2012. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/1853/50135.

Council of Science Editors:

Kemmerlin RK. Carbon molecular sieve membranes for aggressive sour gas separations. [Masters Thesis]. Georgia Tech; 2012. Available from: http://hdl.handle.net/1853/50135

University of Michigan

25. Hutson, Nick D. Synthesis and characterization of novel materials for use as adsorbents in gas separations.

Degree: PhD, Chemical engineering, 2000, University of Michigan

URL: http://hdl.handle.net/2027.42/123516

► Separations using adsorption involve the preferential attraction of one or more solutes from a gas or liquid mixture to the surface of a solid adsorbent… (more)

▼ Separations using adsorption involve the preferential attraction of one or more solutes from a gas or liquid mixture to the surface of a solid adsorbent where they are held by intermolecular forces. This dissertation discusses the synthesis, characterization, and evaluation of several novel materials that may find use as adsorbents in gas separation operations. These materials include silver and mixed silver/lithium zeolites, pillared clays that had been prepared under varying conditions, ion-exchanged pillared clays, and immobilized oxygen-binding organometallic cobalt complexes. The structures of the silver-containing and mixed Li,Ag zeolites were characterized using Rietveld refinement of neutron diffraction data. In both of these cases, a novel silver site, referred to as SII*, was found. This site, because of its distance from the framework oxygen the six-ring and its low valence bond number, interacts with adsorbates such as nitrogen much more than silver in the conventional SII. One mixed Li,Ag-LSX zeolite, containing an average of only one silver per unit cell, was evaluated for its use in the adsorptive separation of air. The results of a PSA cycle simulation predicted that this material gives a >10% improvement in productivity. The oxygen-binding complexes were immobilized on various nanoporous substrates; and the adsorptive capacity and stability were evaluated. The results showed that by immobilizing these complexes on the substrates the adsorptive characteristics were affected. The adsorption isotherms were more linear and had a greater reversibility. Specific synthesis conditions and past-synthesis modification were used to control the micropore structure of alumina-pillared clays. The use of Monte Carlo (MC) techniques to the simulate the adsorption of N₂, O₂, and Ar in the Li-LSX, and the effects of residual zeolitic water on the adsorption of these atmospheric gases in lithium ion-exchanged low silica X zeolite is also discussed. Advisors/Committee Members: Yang, Ralph T. (advisor).

Subjects/Keywords: Adsorbents; Characterization; Gas Separations; Materials; Novel; Silver Clusters; Synthesis; Use; Zeolites

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APA (6^th Edition):

Hutson, N. D. (2000). Synthesis and characterization of novel materials for use as adsorbents in gas separations. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/123516

Chicago Manual of Style (16^th Edition):

Hutson, Nick D. “Synthesis and characterization of novel materials for use as adsorbents in gas separations.” 2000. Doctoral Dissertation, University of Michigan. Accessed April 15, 2021. http://hdl.handle.net/2027.42/123516.

MLA Handbook (7^th Edition):

Hutson, Nick D. “Synthesis and characterization of novel materials for use as adsorbents in gas separations.” 2000. Web. 15 Apr 2021.

Vancouver:

Hutson ND. Synthesis and characterization of novel materials for use as adsorbents in gas separations. [Internet] [Doctoral dissertation]. University of Michigan; 2000. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/2027.42/123516.

Council of Science Editors:

Hutson ND. Synthesis and characterization of novel materials for use as adsorbents in gas separations. [Doctoral Dissertation]. University of Michigan; 2000. Available from: http://hdl.handle.net/2027.42/123516

University of Michigan

26. Smith, Heather Lynne. Vector modeling and tunable selectivity strategies for high-speed gas chromatography.

Degree: PhD, Pure Sciences, 1998, University of Michigan

URL: http://hdl.handle.net/2027.42/131331

► High speed gas chromatograms are obtained using short capillary columns with high carrier gas velocities. This reduces resolution and peak capacity, making separations of complex… (more)

▼ High speed gas chromatograms are obtained using short capillary columns with high carrier gas velocities. This reduces resolution and peak capacity, making separations of complex mixtures difficult. A solution is the use of a polar and nonpolar column in series. Adjusting the pressure at the junction tunes the selectivity within limits imposed by the columns. Using two 5.0m long, 0.25mm i.d. columns, pressure steps of 0.1 psi result in 0.007 changes in the fractional contributions from each column. Using electronic pressure control, up to 100 unique retention patterns are obtained reproducibly. Selectivity programming, where tuning pressure is adjusted during analysis, combined with temperature programming separates 30 compounds with a large boiling point range under 2.5 minutes. A model of multiphase separations is developed and used to optimize isothermal and isobaric tandem column separations. Each mixture component occupies a point in two dimensions, where orthogonal axes represent retention on individual columns. A phase fraction axis is defined from the origin of the retention plane. The angle this axis makes with the orthogonal axes is defined by the fractional contributions to the total holdup time from each column. Coordinates along this axis define retention using column combinations. Mixture component points are connected pairwise by separation vectors. Locator vectors connect the origin to the separation vector centers. Relative resolution is the ratio of projections of the separation and locator vectors onto the phase fraction axis. Minimum values of relative resolution considering all nonredundant pairs are plotted versus phase fraction axis rotation. This window diagram identifies the optimum column combination. A model of column efficiency is developed and validated for high speed gas chromatography using ambient pressure air as carrier gas, driven by vacuum outlet. The system is constrained for a 30 second analysis of analytes with retention factors from 0-5. A range of column diameters is considered. The best results are obtained with a 0.1 mm i.d. column, which is predicted to produce up to 25,000 plates under the given constraints. Advisors/Committee Members: Sacks, Richard D. (advisor).

Subjects/Keywords: Column Retention; Gas Chromatography; High; Modeling; Multiphase Separations; Speed; Strategies; Tunable Selectivity; Vector

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APA (6^th Edition):

Smith, H. L. (1998). Vector modeling and tunable selectivity strategies for high-speed gas chromatography. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/131331

Chicago Manual of Style (16^th Edition):

Smith, Heather Lynne. “Vector modeling and tunable selectivity strategies for high-speed gas chromatography.” 1998. Doctoral Dissertation, University of Michigan. Accessed April 15, 2021. http://hdl.handle.net/2027.42/131331.

MLA Handbook (7^th Edition):

Smith, Heather Lynne. “Vector modeling and tunable selectivity strategies for high-speed gas chromatography.” 1998. Web. 15 Apr 2021.

Vancouver:

Smith HL. Vector modeling and tunable selectivity strategies for high-speed gas chromatography. [Internet] [Doctoral dissertation]. University of Michigan; 1998. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/2027.42/131331.

Council of Science Editors:

Smith HL. Vector modeling and tunable selectivity strategies for high-speed gas chromatography. [Doctoral Dissertation]. University of Michigan; 1998. Available from: http://hdl.handle.net/2027.42/131331

University of Guelph

27. Beach, Daniel. Non-Target Chemical Analysis Using Liquid Chromatography, Differential Ion Mobility and Tandem Mass Spectrometry.

Degree: PhD, Department of Chemistry, 2013, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/6571

► Identification of trace unknown analytes in complex samples remains a significant challenge for analytical chemistry. Mass spectrometry (MS) and analytical separations techniques can now be… (more)

▼ Identification of trace unknown analytes in complex samples remains a significant challenge for analytical chemistry. Mass spectrometry (MS) and analytical separations techniques can now be used to develop and support a new analytical strategy called non-target analysis which aims to provide comprehensive identification and quantification of all detectable chemical species in a complex sample. This thesis addresses challenges currently limiting the utility of this non-target approach by developing analytical methods for acquiring MS data suitable for identification of trace unknowns and investigating current tools available for unknown identification from MS spectral data. Liquid chromatography (LC) - MS, a widely used technique in trace analysis, was used to develop an analytical method capable of simultaneously acquiring high resolution MS and tandem mass spectrometry (MS/MS) data for hundreds of metabolites in urine. An emerging separation technique called high field asymmetric waveform ion mobility spectrometry (FAIMS) was also investigated, as an alternative to LC, for the identification of non-target analytes in urine. Modifications were carried out to the FAIMS-MS source interface allowing for transmission of small metabolite ions from FAIMS to MS. The challenge of direct electrospray (ESI) in urine analysis using ESI-FAIMS-MS was addressed by using sample dilution and extending MS data acquisition time using FAIMS. This allowed for higher quality MS data to be acquired for low abundance urinary metabolites than was possible by LC-MS and the complete elimination of ionization suppression in dilute urine samples. Insight gained into ESI suppression in complex samples allowed for two methods of semi-quantification to be proposed for non-target analytes in complex samples without using unavailable chemical standards. To address the challenge of unknown identification, faced throughout this thesis, an integrated approach was implemented to identify metabolites based only on spectral data without the usual requirement of availability of chemical standards. This approach combined spectral libraries, literature reports on ion chemistry and de novo identification based on gas phase ion chemistry with a detailed fragmentation study on nucleic acid bases, notably protonated uracil. Together, the instrumental methods and approaches to data analysis described allowed for the identification of 110 abundant chemical species detected in urine. Advisors/Committee Members: Gabryelski, Wojciech (advisor).

Subjects/Keywords: FAIMS; High Field Asymmetric Waveform Ion Mobility Spectrometry; Analytical Chemistry; Unknonwn Identification; Separations; Gas Phase Ion Chemistry; Differential Mobility Spectrometry; Mass Spectrometry; Metabolomics; Urine

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APA (6^th Edition):

Beach, D. (2013). Non-Target Chemical Analysis Using Liquid Chromatography, Differential Ion Mobility and Tandem Mass Spectrometry. (Doctoral Dissertation). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/6571

Chicago Manual of Style (16^th Edition):

Beach, Daniel. “Non-Target Chemical Analysis Using Liquid Chromatography, Differential Ion Mobility and Tandem Mass Spectrometry.” 2013. Doctoral Dissertation, University of Guelph. Accessed April 15, 2021. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/6571.

MLA Handbook (7^th Edition):

Beach, Daniel. “Non-Target Chemical Analysis Using Liquid Chromatography, Differential Ion Mobility and Tandem Mass Spectrometry.” 2013. Web. 15 Apr 2021.

Vancouver:

Beach D. Non-Target Chemical Analysis Using Liquid Chromatography, Differential Ion Mobility and Tandem Mass Spectrometry. [Internet] [Doctoral dissertation]. University of Guelph; 2013. [cited 2021 Apr 15]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/6571.

Council of Science Editors:

Beach D. Non-Target Chemical Analysis Using Liquid Chromatography, Differential Ion Mobility and Tandem Mass Spectrometry. [Doctoral Dissertation]. University of Guelph; 2013. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/6571

28. Kraftschik, Brian E. Advanced crosslinkable polyimide membranes for aggressive sour gas separations.

Degree: PhD, Chemical and Biomolecular Engineering, 2013, Georgia Tech

URL: http://hdl.handle.net/1853/52964

► The glassy copolyimide 6FDA-DAM:DABA was investigated as a polymer backbone for membranes used in aggressive sour gas separation applications. An esterification crosslinking mechanism enabled the… (more)

Subjects/Keywords: Sour gas separations; Polyimide membranes; Asymmetric hollow fiber membranes

…172 4.2. Application of Glassy Polymer Membranes to Sour Gas Separations...... 127 4.3… …169 5. CROSSLINKABLE POLYIMIDE MATERIALS FOR AGGRESSIVE SOUR GAS SEPARATIONS… …261 x 7. SOUR GAS SEPARATIONS WITH CROSSLINKABLE PEGMC ASYMMETRIC HOLLOW FIBER MEMBRANES… …294 8.1.1. Benchmarking an Advanced Polyimide for Sour Gas Separations .. 294 8.1.2… …189 Table 5.7: Ideal selectivity values for sour gas separations in crosslinked PEGMC and…

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APA (6^th Edition):

Kraftschik, B. E. (2013). Advanced crosslinkable polyimide membranes for aggressive sour gas separations. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/52964

Chicago Manual of Style (16^th Edition):

Kraftschik, Brian E. “Advanced crosslinkable polyimide membranes for aggressive sour gas separations.” 2013. Doctoral Dissertation, Georgia Tech. Accessed April 15, 2021. http://hdl.handle.net/1853/52964.

MLA Handbook (7^th Edition):

Kraftschik, Brian E. “Advanced crosslinkable polyimide membranes for aggressive sour gas separations.” 2013. Web. 15 Apr 2021.

Vancouver:

Kraftschik BE. Advanced crosslinkable polyimide membranes for aggressive sour gas separations. [Internet] [Doctoral dissertation]. Georgia Tech; 2013. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/1853/52964.

Council of Science Editors:

Kraftschik BE. Advanced crosslinkable polyimide membranes for aggressive sour gas separations. [Doctoral Dissertation]. Georgia Tech; 2013. Available from: http://hdl.handle.net/1853/52964

29. Horn, Norman Randall. Carbon dioxide plasticization and conditioning of thin glassy polymer films monitored by gas permeability and optical methods.

Degree: PhD, Chemical Engineering, 2012, University of Texas – Austin

URL: http://hdl.handle.net/2152/ETD-UT-2012-05-5261

► This research project investigated physical aging and carbon dioxide plasticization behavior of glassy polymer films. Recent studies have shown that thin glassy polymer films undergo… (more)

▼ This research project investigated physical aging and carbon dioxide plasticization behavior of glassy polymer films. Recent studies have shown that thin glassy polymer films undergo physical aging more rapidly than thick films. This suggests that thickness may also play a role in the plasticization and conditioning responses of thin glassy films in the presence of highly-sorbing penetrants such as CO₂. The effect of film thickness on CO₂ permeation and sorption was studied extensively through carefully defined and controlled methods that provide a basis for future study of plasticization behavior. Thin films are found to be more sensitive than thick films to CO₂ exposure, undergoing more extensive and rapid plasticization at any pressure. The response of glassy polymers films to CO₂ is not only dependent on thickness, but also on aging time, CO₂ pressure, exposure time, and prior history. Thin films experiencing constant CO₂ exposure for longer periods of time exhibit an initial large increase in CO₂ permeability, which eventually reaches a maximum, followed by a significant decrease in permeability for the duration of the experiment. Thick films, in contrast, do not seem to exhibit this trend for the range of conditions explored. For a series of different polymers, the extent of plasticization response tracks with CO₂ solubility. There is little data available for gas sorption in thin glassy polymer films. In this work, a novel method involving spectroscopic ellipsometry is used to obtain simultaneously the film thickness and CO₂ sorption capacity for thin glassy polymer films. This allows a more comprehensive look at CO₂ permeability, sorption, and diffusivity as a function of both CO₂ pressure and exposure time. Like the gas permeation data, these experiments suggest that thin film sorption behavior is substantially different than that of thick film counterparts. Dynamic ellipsometry experiments show that refractive index minima, fractional free volume maxima, and CO₂ diffusivity maxima correlate well with observed CO₂ permeability maxima observed for thin Matrimid® films. These experiments demonstrate that plasticization and physical aging are competing processes. Aging, however, dominates over long time scales. Over time, CO₂ diffusivity is most affected by these competing effects, and the evolution of CO₂ diffusivity is shown to be the main contributing factor to changes in CO₂ permeability at constant pressure. Advisors/Committee Members: Paul, Donald R. (advisor), Freeman, Benny (committee member), Biewlawski, Chris (committee member), Ellison, Christopher J. (committee member), Sanchez, Isaac (committee member).

Subjects/Keywords: Plasticization; Physical aging; Carbon dioxide; Thin films; Gas separations

…membrane separations [1]. Gas transport in non-porous polymeric membranes occurs via a… …response tracks with CO2 solubility. There is little data available for gas sorption in thin… …diffusivity as a function of both CO2 pressure and exposure time. Like the gas permeation data… …9 2.1 Membrane Separations… …Sorption Behavior .... 17 2.6 Determining Thickness, Optical Properties, and Gas Sorption with…

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APA (6^th Edition):

Horn, N. R. (2012). Carbon dioxide plasticization and conditioning of thin glassy polymer films monitored by gas permeability and optical methods. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/ETD-UT-2012-05-5261

Chicago Manual of Style (16^th Edition):

Horn, Norman Randall. “Carbon dioxide plasticization and conditioning of thin glassy polymer films monitored by gas permeability and optical methods.” 2012. Doctoral Dissertation, University of Texas – Austin. Accessed April 15, 2021. http://hdl.handle.net/2152/ETD-UT-2012-05-5261.

MLA Handbook (7^th Edition):

Horn, Norman Randall. “Carbon dioxide plasticization and conditioning of thin glassy polymer films monitored by gas permeability and optical methods.” 2012. Web. 15 Apr 2021.

Vancouver:

Horn NR. Carbon dioxide plasticization and conditioning of thin glassy polymer films monitored by gas permeability and optical methods. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2012. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/2152/ETD-UT-2012-05-5261.

Council of Science Editors:

Horn NR. Carbon dioxide plasticization and conditioning of thin glassy polymer films monitored by gas permeability and optical methods. [Doctoral Dissertation]. University of Texas – Austin; 2012. Available from: http://hdl.handle.net/2152/ETD-UT-2012-05-5261

University of Michigan

30. McGuigan, Megan Ellen. Optimization and application of selectivity enhancement techniques for GC separations using series-coupled dual column ensembles.

Degree: PhD, Pure Sciences, 2005, University of Michigan

URL: http://hdl.handle.net/2027.42/124886

► Recent research in Gas Chromatography (GC) has focused in the areas of high-speed separations, micro-fabrication and methods development for the analysis of mixtures containing large… (more)

▼ Recent research in Gas Chromatography (GC) has focused in the areas of high-speed separations, micro-fabrication and methods development for the analysis of mixtures containing large numbers of components. Methods for high-speed separations often involve the use of shorter columns, high carrier gas velocities, micro-bore columns and fast temperature-programming. While these methods do reduce analysis times, their applications are limited. Common test mixtures for GC analysis may contain up to several hundred components and with shorter columns, the peak capacity is limited and therefore the resolving power is decreased. The development of methods for the more efficient use of the available peak capacity is therefore of great interest. The development of selectivity enhancement techniques using pneumatic and thermal methods on a series-coupled dual-column ensemble is discussed. By controlling the carrier gas flow or temperature on each of the two columns, peaks can be separated at the ensemble outlet that would otherwise co-elute. Methods presented include pressure-pulse modulation, stop-flow operation, at-column heating and zone heating. A spreadsheet-based model was used to study experimental parameters and to design experimental methods. This model uses a series of equations to calculate carrier gas velocity, temperature, carrier gas viscosity, retention factors and time as a function of solute position over the length of the column. The model results in a band-trajectory plot that shows the path each solute takes from injection to elution. Comprehensive two-dimensional GC (GC x GC) is an emerging technique that offers both an increased peak capacity and detectability. Using this method, sample components are separated in two orthogonal dimensions, resulting in a chromatogram in which peaks are displayed across a two-dimensional plane. Samples studied using this technique include tholin, a synthetic analogue to the atmospheric haze particles that surround Titan, soils, minerals and meteorites. A pyrolysis inlet system was used so that samples that would not otherwise be suitable for GC analysis could be studied, and TOF-MS detection was used for peak identification. These samples were chosen for their complex nature and for their similarity to the mixtures that may be observed by the 2009 Mars Science Laboratory (MSL) mission. Advisors/Committee Members: Sacks, Richard D. (advisor).

Subjects/Keywords: Application; Coupled; Dual Column; Enhancement; Ensembles; Gas Chromatography; Gc; Optimization; Selectivity; Separations; Series; Techniques; Using

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

McGuigan, M. E. (2005). Optimization and application of selectivity enhancement techniques for GC separations using series-coupled dual column ensembles. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/124886

Chicago Manual of Style (16^th Edition):

McGuigan, Megan Ellen. “Optimization and application of selectivity enhancement techniques for GC separations using series-coupled dual column ensembles.” 2005. Doctoral Dissertation, University of Michigan. Accessed April 15, 2021. http://hdl.handle.net/2027.42/124886.

MLA Handbook (7^th Edition):

McGuigan, Megan Ellen. “Optimization and application of selectivity enhancement techniques for GC separations using series-coupled dual column ensembles.” 2005. Web. 15 Apr 2021.

Vancouver:

McGuigan ME. Optimization and application of selectivity enhancement techniques for GC separations using series-coupled dual column ensembles. [Internet] [Doctoral dissertation]. University of Michigan; 2005. [cited 2021 Apr 15]. Available from: http://hdl.handle.net/2027.42/124886.

Council of Science Editors:

McGuigan ME. Optimization and application of selectivity enhancement techniques for GC separations using series-coupled dual column ensembles. [Doctoral Dissertation]. University of Michigan; 2005. Available from: http://hdl.handle.net/2027.42/124886

Open Access Theses and Dissertations