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Limitations and high pressure behavior of MOF-5 for CO2 capture
J. Y. Jung,‡ F. Karadas,‡ S. Zulfiqar,‡ E. Deniz, S. Aparicio, M. Atilhan*, C. T. Yavuz*, S. M. Han*
Phys. Chem. Chem. Phys., 15, 14319-14327, (2013). [pdf] [DOI] [WOS] (‡ Equal contribution)
Phys. Chem. Chem. Phys., 15, 14319-14327, (2013). [pdf] [DOI] [WOS] (‡ Equal contribution)
Influence of aminosilane coupling agent on aromatic polyamide/intercalated clay nanocomposites
M. U. Alvi, S. Zulfiqar*, C. T. Yavuz, H.-S. Kweon, M. I. Sarwar*
Ind. Eng. Chem. Res., 52 (21), 6908–6915, (2013). [DOI] [pdf] [WOS]
Aminosilane grafted and 1,4-phenylene diamine modified reactive montmorillonite was exploited for the generation of aromatic polyamide-layered silicate nanocomposites. For better compatibility between the two disparate phases, the hydrophilic nature of montmorillonite was changed into organophilic by ion-exchange method using 1,4-phenylenediamine as an intercalating agent and the hydroxyl groups present on clay surface and edges were used to graft 3-aminopropyltriethoxysilane (APTS) on clay platelets. The dispersion behavior of reactive organoclay was monitored in the polyamide matrix prepared from a pair of diamines (1,4-phenylenediamine and 4-4′-oxydianiline) with isophthaloyl chloride under anhydrous conditions. The resulting chains were selectively converted into carbonyl chloride ends to interact exclusively with free amine groups of the 1,4-phenylenediamine and APTS grafted on nanoclay. Thin composite films containing 2 to 10-wt. % clay were probed for FTIR, XRD, SEM, TEM, tensile testing, TGA and DSC measurements. XRD and TEM results described ample dispersion and morphology of clay sheets in the nanocomposites. Mechanical measurements revealed that tensile strength increased 110 %, elongation 172 % while modulus and toughness augmented many folds upon the addition of 4-6 wt. % clay in the matrix. Thermal decomposition temperatures of the nanocomposites were in the range 425-480 oC. The glass transition temperature increased up to 142.4 oC with 6-wt. % addition of organoclay in the matrix relative to pure polyamide depicting interfacial interactions among the phases.
Ind. Eng. Chem. Res., 52 (21), 6908–6915, (2013). [DOI] [pdf] [WOS]
Aminosilane grafted and 1,4-phenylene diamine modified reactive montmorillonite was exploited for the generation of aromatic polyamide-layered silicate nanocomposites. For better compatibility between the two disparate phases, the hydrophilic nature of montmorillonite was changed into organophilic by ion-exchange method using 1,4-phenylenediamine as an intercalating agent and the hydroxyl groups present on clay surface and edges were used to graft 3-aminopropyltriethoxysilane (APTS) on clay platelets. The dispersion behavior of reactive organoclay was monitored in the polyamide matrix prepared from a pair of diamines (1,4-phenylenediamine and 4-4′-oxydianiline) with isophthaloyl chloride under anhydrous conditions. The resulting chains were selectively converted into carbonyl chloride ends to interact exclusively with free amine groups of the 1,4-phenylenediamine and APTS grafted on nanoclay. Thin composite films containing 2 to 10-wt. % clay were probed for FTIR, XRD, SEM, TEM, tensile testing, TGA and DSC measurements. XRD and TEM results described ample dispersion and morphology of clay sheets in the nanocomposites. Mechanical measurements revealed that tensile strength increased 110 %, elongation 172 % while modulus and toughness augmented many folds upon the addition of 4-6 wt. % clay in the matrix. Thermal decomposition temperatures of the nanocomposites were in the range 425-480 oC. The glass transition temperature increased up to 142.4 oC with 6-wt. % addition of organoclay in the matrix relative to pure polyamide depicting interfacial interactions among the phases.
+
2013,
KAIST,
Polymer,
Publications,
Sonia
Phosphorus stimulated unidirectional growth of TiO2 nanostructures
L. White, M. Kim, J. Zhang, S. Kraemer, C. T. Yavuz, M. Moskovits, A. M. Wodtke, G. D. Stucky*
J. Mater. Chem. A, 1, 6091-6098, (2013). [DOI] [pdf] [WOS]
Previously reported TiO2 nanowire fabrication from Ni catalysts shows a surprising amount of phosphorous (P) contamination incorporated into the seed particle. We proposed this unintentional P-doping of Ni particles aids the mechanism for nanowire growth and occurs by an alternative pathway from the Vapor–Liquid–Solid (VLS) mechanism. To confirm this new mechanism, mixed phase NiP/Ni2P (NixPy) and Ni2P nanoparticles were fabricated and the central role of phosphorous in TiO2 nanowire synthesis confirmed. This newly developed P-assisted fabrication method yielded crystalline rutile TiO2 nanowires. In this mechanism solid, quasi-spherical catalyst particles attached to the ends of nanowires and surrounded by a Ni/P liquid shell are responsible for the nanowire growth. The growing end of the nanowire appears to form a “tangent-plane” to the solid catalyst core with the liquid shell wetting and occupying the interstice between the catalyst and the nanowire. In NixPy assisted growth, nanowire diameters occurred as small as 12.3 nm, some of the thinnest yet reported TiO2 nanowires resulting from atmospheric-pressure chemical vapor deposition (APCVD) growth.
J. Mater. Chem. A, 1, 6091-6098, (2013). [DOI] [pdf] [WOS]
Previously reported TiO2 nanowire fabrication from Ni catalysts shows a surprising amount of phosphorous (P) contamination incorporated into the seed particle. We proposed this unintentional P-doping of Ni particles aids the mechanism for nanowire growth and occurs by an alternative pathway from the Vapor–Liquid–Solid (VLS) mechanism. To confirm this new mechanism, mixed phase NiP/Ni2P (NixPy) and Ni2P nanoparticles were fabricated and the central role of phosphorous in TiO2 nanowire synthesis confirmed. This newly developed P-assisted fabrication method yielded crystalline rutile TiO2 nanowires. In this mechanism solid, quasi-spherical catalyst particles attached to the ends of nanowires and surrounded by a Ni/P liquid shell are responsible for the nanowire growth. The growing end of the nanowire appears to form a “tangent-plane” to the solid catalyst core with the liquid shell wetting and occupying the interstice between the catalyst and the nanowire. In NixPy assisted growth, nanowire diameters occurred as small as 12.3 nm, some of the thinnest yet reported TiO2 nanowires resulting from atmospheric-pressure chemical vapor deposition (APCVD) growth.
+
2013,
KAIST,
Nano,
Publications
A combined computational and experimental study of high pressure and supercritical CO2 adsorption on Basolite MOFs
E. Deniz, F. Karadas, H. A. Patel, S. Aparicio*, C. T. Yavuz*, M. Atilhan*
Micropor. Mesopor. Mat., 175, 34-42 (2013). [DOI] [pdf] [WOS]
Metal organic frameworks (such as commercial Basolite®) display significant promise for CO2 capture and storage. Here, in order to monitor CO2 capture of Basolite®, we combined high pressure CO2 adsorption with high-pressure FTIR and Monte Carlo simulations. We found that Basolite® C300 show an unprecedented rise in capture capacity above 25 bars, as predicted by the DFT calculations. Adsorption isotherms were measured up to 200 bar using a state-of-the-art magnetic suspension balance, and in-situ FTIR studies as a function of pressure allowed characterizing the preferential adsorption sites, and their occupancy with increasing pressure. Monte Carlo molecular simulations were used to infer nanoscopic information of the adsorption mechanism, showing the sorbent–CO2 interactions from structural and energetic viewpoints.
Click here to access via the publisher
Micropor. Mesopor. Mat., 175, 34-42 (2013). [DOI] [pdf] [WOS]
Metal organic frameworks (such as commercial Basolite®) display significant promise for CO2 capture and storage. Here, in order to monitor CO2 capture of Basolite®, we combined high pressure CO2 adsorption with high-pressure FTIR and Monte Carlo simulations. We found that Basolite® C300 show an unprecedented rise in capture capacity above 25 bars, as predicted by the DFT calculations. Adsorption isotherms were measured up to 200 bar using a state-of-the-art magnetic suspension balance, and in-situ FTIR studies as a function of pressure allowed characterizing the preferential adsorption sites, and their occupancy with increasing pressure. Monte Carlo molecular simulations were used to infer nanoscopic information of the adsorption mechanism, showing the sorbent–CO2 interactions from structural and energetic viewpoints.
Click here to access via the publisher
+
2013,
CO2,
Environmental,
Hasmukh,
KAIST,
Mert,
MOFs,
Publications
Unprecedented high-temperature CO2 selectivity in N2-phobic nanoporous covalent organic polymers
H. A. Patel, S. H. Je, J. Park, D. P. Chen, Y. Jung, C. T. Yavuz*, A. Coskun*
Nature Commun., 4, 1357, (2013). [DOI] [pdf] [WOS]
Post-combustion CO2 capture and air separation are integral parts of the energy industry, although the available technologies remain inefficient, resulting in costly energy penalties. Here we report azo-bridged, nitrogen-rich, aromatic, water stable, nanoporous covalent organic polymers, which can be synthesized by catalyst-free direct coupling of aromatic nitro and amine moieties under basic conditions. Unlike other porous materials, azo-covalent organic polymers exhibit an unprecedented increase in CO2/N2 selectivity with increasing temperature, reaching the highest value (288 at 323 K) reported to date. Here we observe that azo groups reject N2, thus making the framework N2-phobic. Monte Carlo simulations suggest that the origin of the N2 phobicity of the azo-group is the entropic loss of N2 gas molecules upon binding, although the adsorption is enthalpically favourable. Any gas separations that require the efficient exclusion of N2 gas would do well to employ azo units in the sorbent chemistry.
Nature Commun., 4, 1357, (2013). [DOI] [pdf] [WOS]
With CO2/N2 selectivity of 288, Azo-COP-2 (COP-69) holds the current world record
Highlighted in Chemical & Engineering News, Chemistry World, Yeni Asir (Turkish)(another link), Aktif Haber (Turkish), Zaman (Turkish), Bugun (Turkish), Enerji Enstitusu (Turkish), Daejeon Ilbo (Korean), MK News (Korean), Yonhap News (Korean)
Highlighted in Chemical & Engineering News, Chemistry World, Yeni Asir (Turkish)(another link), Aktif Haber (Turkish), Zaman (Turkish), Bugun (Turkish), Enerji Enstitusu (Turkish), Daejeon Ilbo (Korean), MK News (Korean), Yonhap News (Korean)
Post-combustion CO2 capture and air separation are integral parts of the energy industry, although the available technologies remain inefficient, resulting in costly energy penalties. Here we report azo-bridged, nitrogen-rich, aromatic, water stable, nanoporous covalent organic polymers, which can be synthesized by catalyst-free direct coupling of aromatic nitro and amine moieties under basic conditions. Unlike other porous materials, azo-covalent organic polymers exhibit an unprecedented increase in CO2/N2 selectivity with increasing temperature, reaching the highest value (288 at 323 K) reported to date. Here we observe that azo groups reject N2, thus making the framework N2-phobic. Monte Carlo simulations suggest that the origin of the N2 phobicity of the azo-group is the entropic loss of N2 gas molecules upon binding, although the adsorption is enthalpically favourable. Any gas separations that require the efficient exclusion of N2 gas would do well to employ azo units in the sorbent chemistry.
+
2013,
CO2,
COPs,
Coskun,
Environmental,
Hasmukh,
Jung,
KAIST,
Open,
Publications
Highly Stable Nanoporous Sulfur bridged Covalent Organic Polymers for Carbon Dioxide Removal
H. A. Patel, F. Karadas, J. Byun, J. Park, E. Deniz, A. Canlier, Y. Jung,* M. Atilhan*, C. T. Yavuz*
Adv. Funct. Mater., 23, 2270–2276 (2013). [DOI] [pdf]
Carbon dioxide capture and separation requires robust solids that can stand harsh environments where a hot mixture of gases is often found. Herein, the first and comprehensive syntheses of porous sulfur-bridged covalent organic polymers (COPs) and their application for carbon dioxide capture in warm conditions and a wide range of pressures (0–200 bar) are reported. These COPs can store up to 3294 mg g−1 of carbon dioxide at 318 K and 200 bar while being highly stable against heating up to 400 °C. The carbon dioxide capacity of the COPs is also not hindered upon boiling in water for at least one week. Physisorptive binding is prevalent with isosteric heat of adsorptions around 24 kJ mol−1. M06–2X and RIMP2 calculations yield the same relative trend of binding energies, where, interestingly, the dimer of triazine and benzene play a cooperative role for a stronger binding of CO2 (19.2 kJ mol−1) as compared to a separate binding with triazine (13.3 kJ mol−1) or benzene (11.8 kJ mol−1).
Click here for the supporting information
Adv. Funct. Mater., 23, 2270–2276 (2013). [DOI] [pdf]
Carbon dioxide capture and separation requires robust solids that can stand harsh environments where a hot mixture of gases is often found. Herein, the first and comprehensive syntheses of porous sulfur-bridged covalent organic polymers (COPs) and their application for carbon dioxide capture in warm conditions and a wide range of pressures (0–200 bar) are reported. These COPs can store up to 3294 mg g−1 of carbon dioxide at 318 K and 200 bar while being highly stable against heating up to 400 °C. The carbon dioxide capacity of the COPs is also not hindered upon boiling in water for at least one week. Physisorptive binding is prevalent with isosteric heat of adsorptions around 24 kJ mol−1. M06–2X and RIMP2 calculations yield the same relative trend of binding energies, where, interestingly, the dimer of triazine and benzene play a cooperative role for a stronger binding of CO2 (19.2 kJ mol−1) as compared to a separate binding with triazine (13.3 kJ mol−1) or benzene (11.8 kJ mol−1).
Click here for the supporting information
High Pressure CO2 Absorption Studies on Imidazolium Based Ionic Liquids: Experimental and Simulation Approaches
F. Karadas, B. Köz, J. Jacquemin, E. Deniz, D. Rooney, J. Thompson, C. T. Yavuz, M. Khraisheh, S. Aparicio*, M. Atihan*
Fluid Phase Equilibria, 351, 74–86 (2013). [DOI] [pdf]
A combined experimental–computational study on the CO2 absorption on 1-butyl-3-methylimidazolium hexafluophosphate, 1-ethyl-3-methylimidazolium bis[trifluoromethylsulfonyl]imide, and 1-butyl-3-methylimidazolium bis[trifluoromethylsulfonyl]imide ionic liquids is reported. The reported results allowed to infer a detailed nanoscopic vision of the absorption phenomena as a function of pressure and temperature. Absorption isotherms were measured at 318 and 338 K for pressures up to 20 MPa for ultrapure samples using a state-of-the-art magnetic suspension densimeter, for which measurement procedures are developed. A remarkable swelling effect upon CO2 absorption was observed for pressures higher than 10 MPa, which was corrected using a method based on experimental volumetric data. The experimental data reported in this work are in good agreement with available literature isotherms. Soave–Redlich–Kwong and Peng–Robinson equations of state coupled with bi-parametric van der Waals mixing rule were used for successful correlations of experimental high pressure absorption data. Molecular dynamics results allowed to infer structural, energetic and dynamic properties of the studied CO2 + ionic liquids mixed fluids, showing the relevant role of the strength of anion–cation interactions on fluid volumetric properties and CO2 absorption.
Keywords
Ionic liquids; High-pressure; Carbon dioxide; Solubility; Imidazolium; Molecular dynamics
A combined experimental–computational study on the CO2 absorption on 1-butyl-3-methylimidazolium hexafluophosphate, 1-ethyl-3-methylimidazolium bis[trifluoromethylsulfonyl]imide, and 1-butyl-3-methylimidazolium bis[trifluoromethylsulfonyl]imide ionic liquids is reported. The reported results allowed to infer a detailed nanoscopic vision of the absorption phenomena as a function of pressure and temperature. Absorption isotherms were measured at 318 and 338 K for pressures up to 20 MPa for ultrapure samples using a state-of-the-art magnetic suspension densimeter, for which measurement procedures are developed. A remarkable swelling effect upon CO2 absorption was observed for pressures higher than 10 MPa, which was corrected using a method based on experimental volumetric data. The experimental data reported in this work are in good agreement with available literature isotherms. Soave–Redlich–Kwong and Peng–Robinson equations of state coupled with bi-parametric van der Waals mixing rule were used for successful correlations of experimental high pressure absorption data. Molecular dynamics results allowed to infer structural, energetic and dynamic properties of the studied CO2 + ionic liquids mixed fluids, showing the relevant role of the strength of anion–cation interactions on fluid volumetric properties and CO2 absorption.
Keywords
Ionic liquids; High-pressure; Carbon dioxide; Solubility; Imidazolium; Molecular dynamics
+
2013,
CO2,
Environmental,
KAIST,
Mert,
Publications
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