Acetylene Sorption Research Articles

Rücktitelbild: Optimizing Acetylene Sorption through Induced‐fit Transformations in a Chemically Stable Microporous Framework (Angew. Chem. 7/2023)

Rücktitelbild: Optimizing Acetylene Sorption through Induced‐fit Transformations in a Chemically Stable Microporous Framework (Angew. Chem. 7/2023)

Back Cover: Optimizing Acetylene Sorption through Induced‐fit Transformations in a Chemically Stable Microporous Framework (Angew. Chem. Int. Ed. 7/2023)

Back Cover: Optimizing Acetylene Sorption through Induced‐fit Transformations in a Chemically Stable Microporous Framework (Angew. Chem. Int. Ed. 7/2023)

Optimizing Acetylene Sorption through Induced‐fit Transformations in a Chemically Stable Microporous Framework

AbstractDeveloping practical storage technologies for acetylene (C2H2) is important but challenging because C2H2 is useful but explosive. Here, a novel metal–organic framework (MOF) (FJI‐H36) with adaptive channels was prepared. It can effectively capture C2H2 (159.9 cm3 cm−3) at 1 atm and 298 K, possessing a record‐high storage density (561 g L−1) but a very low adsorption enthalpy (28 kJ mol−1) among all the reported MOFs. Structural analyses show that such excellent adsorption performance comes from the synergism of active sites, flexible framework, and matched pores; where the adsorbed‐C2H2 can drive FJI‐H36 to undergo induced‐fit transformations step by step, including deformation/reconstruction of channels, contraction of pores, and transformation of active sites, finally leading to dense packing of C2H2. Moreover, FJI‐H36 has excellent chemical stability and recyclability, and can be prepared on a large scale, enabling it as a practical adsorbent for C2H2. This will provide a useful strategy for developing practical and efficient adsorbents for C2H2 storage.

Optimizing Acetylene Sorption through Induced-fit Transformations in a Chemically Stable Microporous Framework.

Developing practical storage technologies for acetylene (C2 H2 ) is important but challenging because C2 H2 is useful but explosive. Here, a novel metal-organic framework (MOF) (FJI-H36) with adaptive channels was prepared. It can effectively capture C2 H2 (159.9 cm3 cm-3 ) at 1 atm and 298 K, possessing a record-high storage density (561 g L-1 ) but a very low adsorption enthalpy (28 kJ mol-1 ) among all the reported MOFs. Structural analyses show that such excellent adsorption performance comes from the synergism of active sites, flexible framework, and matched pores; where the adsorbed-C2 H2 can drive FJI-H36 to undergo induced-fit transformations step by step, including deformation/reconstruction of channels, contraction of pores, and transformation of active sites, finally leading to dense packing of C2 H2 . Moreover, FJI-H36 has excellent chemical stability and recyclability, and can be prepared on a large scale, enabling it as a practical adsorbent for C2 H2 . This will provide a useful strategy for developing practical and efficient adsorbents for C2 H2 storage.

Tunable acetylene sorption by flexible catenated metal-organic frameworks.

The safe storage of flammable gases, such as acetylene, is essential for current industrial purposes. However, the narrow pressure (P) and temperature range required for the industrial use of pure acetylene (100 < P < 200 kPa at 298 K) and its explosive behaviour at higher pressures make its storage and release challenging. Flexible metal-organic frameworks that exhibit a gated adsorption/desorption behaviour-in which guest uptake and release occur above threshold pressures, usually accompanied by framework deformations-have shown promise as storage adsorbents. Herein, the pressures for gas uptake and release of a series of zinc-based mixed-ligand catenated metal-organic frameworks were controlled by decorating its ligands with two different functional groups and changing their ratio. This affects the deformation energy of the framework, which in turn controls the gated behaviour. The materials offer good performances for acetylene storage with a usable capacity of ~90 v/v (77% of the overall amount) at 298 K and under a practical pressure range (100-150 kPa).

Highly selective room temperature acetylene sorption by an unusual triacetylenic phosphine MOF.

The new ligand tris(p-carboxyphenylethynyl)phosphine (P{C[triple bond, length as m-dash]CC6H4-4-CO2H}3) was used to synthesize a permanently porous Mn(ii)-based acetylenic phosphine coordination material, PCM-48. This triply-interpenetrated MOF contains 1-D microchannels that are decorated with electron-rich and adsorbate-accessible acetylenic moieties and phosphine lone pairs. PCM-48 has a moderate room-temperature C2H2 adsorption capacity (25.54 cm3 g-1) and displays high separation selectivities for C2H2 over CH4 (C2H2/CH4 = 23.3), CO2 (C2H2/CO2 = 4.3), and N2 (C2H2/N2 = 76.9) at 296 K.

Effect of Coal Grain Size on Sorption Capacity with Respect to Propylene and Acetylene

Propylene and acetylene are released to mine air with the increase in the temperature of self-heating coal. Concentrations of these gases in mine air are applied as indicators of the progress of the self-heating process. Hydrocarbons emitted from the self-ignition center are sorbed on coal, while migrating through the mine workings. Coal crushed during the mining process is characterized by a high sorption capacity, which facilitates the sorption phenomena. This results in the decrease in hydrocarbons content in mine air, and in the subsequent incorrect assessment of the development of the self-heating process. The results of the experimental study on propylene and acetylene sorption on Polish coals acquired from operating coal mines are presented in this paper. Bituminous coal is characterized by a high sorption capacity with respect to unsaturated hydrocarbons, like propylene and acetylene. The sorbed volumes depend on the grade of metamorphism, porosity, and chemical characteristics of coal. Low level of metamorphism, increased porosity, and oxygen content result in higher sorption capacity of coals. The reduction in grain size of coals also results in the increased sorption capacity with respect to hydrocarbons. The most significant increase in the volumes of sorbed propylene and acetylene with the decrease in grain class was observed for coals of low porosity, high grade of metamorphism, and low to medium sorption capacities. The 10-fold decrease in coal grain size resulted in the 3 to 6-fold increase in the volume of sorbed propylene, and 2-fold increase for acetylene. The decrease in grain size results in higher accessibility of pore structure, increased pore volume and area, and higher number of active centers interacting with hydrocarbons of dipole characteristics. For coals with low grade metamorphism, high porosity, and high sorption capacity the volumes of sorbed propylene and acetylene increased only slightly with the decrease in coal grain size.

Storage and Sorption Properties of Acetylene in Jungle‐Gym‐Like Open Frameworks

The acetylene-sorption properties of six porous coordination polymers (PCPs), [M(2)(L)(2)(dabco)](n) (dabco=1,4-diazabicyclo[2.2.2]octane, M=Cu(2+) (1), Zn(2+) (2), L=1,4-benzenedicarboxylate (bdc; 1 a, 2 a), 1,4-naphthalenedicarboxylate (ndc; 1 b, 2 b), 9,10-anthracenedicarboxylate (adc; 1 c, 2 c)), were investigated. The acetylene sorption isotherms of 1 and 2 measured at 195 K are of type I and show a steep increase at low relative pressures. The sorption properties of carbon dioxide at 195 K were also investigated. Compounds 1 and 2 showed a large difference in onset pressure between acetylene sorption isotherms, although the difference between the carbon dioxide sorption isotherms is not so significant. In particular, 2 c displayed a remarkable affinity for acetylene. The acetylene sorption isotherm at 298 K showed that the adsorption amounts for 2 c and 2 b at 298 K, 1 atm (101 and 106 mL g(-1), respectively) were higher than those of other conventional porous materials. Notably, of the compounds 1 and 2, the porous crystals 2 c had the highest affinity for acetylene.

Cover Picture: Microporous Magnesium and Manganese Formates for Acetylene Storage and Separation (Chem. Asian J. 4/2007)

Low‐cost and efficient materials that store acetylene with high selectivity are the key to its production, transportation, and delivery. In their Full Paper on page 484 ff., K. Kim and co‐workers demonstrate that microporous magnesium and manganese formates show not only a high capacity for acetylene sorption but also remarkable selectivity over CO2, CH4, N2, O2, and H2 at room temperature. The metal formates discriminate C2H2 and CO2 despite their similar size and physical properties. Single‐crystal X‐ray structure analysis of the acetylene‐adsorbed metal formates reveals two acetylene sorption sites.

Microporous Magnesium and Manganese Formates for Acetylene Storage and Separation

Acetylene sorption of microporous metal formates M(HCOO)2 (M = Mg and Mn) was investigated. Measurements of acetylene sorption at 196, 275, and 298 K showed a Type I isotherm with quick saturation at low pressures, and 50-75 cm3 g(-1) uptake at 1.0 atm. The single-crystal X-ray structure analysis of the acetylene-adsorbed metal formates revealed that acetylene molecules occupy two independent positions in the zigzag channels of the frameworks with a stoichiometry of M(HCOO)2 x 1/3C2H2, which is consistent with the gas sorption experiments. No specific interaction except van der Waals interactions between the adsorbed acetylene molecules and the walls of the frameworks was found. Sorption properties of other gases, including CO2, CH4, N2, O2, and H2, were also investigated. When the temperature was increased to 298 K, the amount of adsorbed acetylene was still above 60 cm3 g(-1) for Mg(HCOO)2 and 50 cm3 g(-1) for Mn(HCOO)2, whereas the uptake of other gases decreased substantially. The microporous metal formates may thus be useful not only for the storage of acetylene but also its separation from other gases at room or slightly higher temperatures.

Acetylene Sorption Dynamics in Carbon Nanotubes

AbstractSingle‐walled and multi‐walled carbon nanotubes (SWNT and MWNT, resp.) were prepared by applying the catalytic chemical vapor deposition (CCVD) technique. Different nanotube samples were obtained from the as‐synthesized carbon/catalyst composites by treatments applied to remove the catalyst and the amorphous carbon. The dynamic and equilibrium adsorption properties of the samples were compared. Acetylene was used as an adsorptive probe. The sorption mass‐transport properties have been characterized by applying the frequency response (FR) technique. Results reflected that the surface functional groups, generated by an oxidative treatment, have significant influence on both the static and the dynamic acetylene sorption properties of the carbon nanotube materials. The rate of acetylene mass transport was governed by the rate of sorption in all the samples, except in MWNT after oxidative treatment, where the intracrystalline diffusion in the nanotubes was the rate‐controlling process.

Equilibrium and dynamics of acetylene sorption in multiwalled carbon nanotubes

Multiwalled carbon nanotubes (MWCNT) were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), and by adsorption of N 2 and acetylene. The dynamics of acetylene sorption was studied by frequency response spectroscopy. The average tube dimension and the shell number were determined from a statistical evaluation of the TEM images. This value agreed with that obtained from XRD via the Scherrer equation only if a shape factor of 0.49 was used. The diffusion of acetylene in the nanotubes of the MWCNT sample was found to be the rate-controlling step of the sorption process. Relationships between the tube dimensions and the equilibrium and dynamic sorption properties were demonstrated.

Crystal structure of an acetylene sorption complex of dehydrated fully Cd 2+-exchanged zeolite X

The crystal structure of an acetylene sorption complex of dehydrated fully Cd 2+-exchanged zeolite X, Cd 46Si 100Al 92O 384 · 28C 2H 2 [ a = 24.874(5) Å], has been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd 3 at 21(1)°C. Cd 46−X was dehydrated at 450°C and 2 × 10 −6 Torr for 2 d, followed by exposure to ca. 250 Torr of acetylene gas at 21(1)°C. The structure was determined in this atmosphere and was refined to the final error indices R 1 = 0.058 and R 2 = 0.067 with 661 reflections for which I > 3σ( I). In this structure, Cd 2+ ions are found at three crystallographic sites: 13 Cd 2+ ions are at site l, at the centers of the double six-oxygen rings; five Cd 2+ ions lie at site I′, in the sodalite cavity opposite the double six-oxygen rings; and the remaining 28 Cd 2+ ions are at site II, in the supercage near single six-oxygen rings. Each of these 28 is recessed 0.46 Å into the supercage where it coordinates laterally to an acetylene molecule (CC = 1.22(7) Å). These Cd 2+ ions have a distorted tetrahedral environment, 2.192(8) Å from three framework oxygens and 2.79(5)Å from each carbon atom of an acetylene molecule (here counted as a monodentate). As compared to dehydrated Cd 46−X, five Cd 2+ ions have relocated from sites I and II to I′, as they did in Cd 46−X · 28CO, primarily for electrostatic reasons.

Crystal Structures of the Ethylene and Acetylene Sorption Complexes of Fully Ca2+-Exchanged Zeolite X

The crystal structures of the ethylene (Ca46Si100Al92O384·30C2H4, a = 25.003(5) A) and acetylene (Ca46Si100Al92O384·30C2H2, a = 25.013(5) A) sorption complexes of dehydrated fully Ca2+-exchanged zeolite X have been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd3 at 21(1) °C. Their complexes were prepared by dehydration at 380 °C and 2 × 10-6 Torr for 2 days, followed by cooling and exposure to 300 Torr of ethylene or 250 Torr of acetylene gases, respectively, both at 21(1) °C. The structures were determined in these atmospheres and refined to the final error indices, R1 = 0.050 and R2 = 0.051 with 371 reflections, and R1 = 0.049 and R2 = 0.045 with 415 reflections, respectively, for which I > 3σ(I). In each structure, as in dehydrated Ca46−X, 16 Ca2+ ions per unit cell fill site I at the centers of the double six-rings, and the remaining 30 are at site II in the supercages. Thirty ethylene or 30 acetylene molecules are sorbed, all in the supercages, one coordinating...

Crystal structures of acetylene sorption complexes of partially manganese(II)-exchanged and partially cobalt(II)-exchanged forms of zeolite A

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCrystal structures of acetylene sorption complexes of partially manganese(II)-exchanged and partially cobalt(II)-exchanged forms of zeolite APaul E. Riley and Karl. SeffCite this: Inorg. Chem. 1975, 14, 4, 714–721Publication Date (Print):April 1, 1975Publication History Published online1 May 2002Published inissue 1 April 1975https://doi.org/10.1021/ic50146a003RIGHTS & PERMISSIONSArticle Views63Altmetric-Citations24LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (1 MB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

Crystal structure of an acetylene sorption complex of partially manganese(II)-exchanged zeolite A

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCrystal structure of an acetylene sorption complex of partially manganese(II)-exchanged zeolite APaul E. Riley and Karl. SeffCite this: J. Am. Chem. Soc. 1973, 95, 24, 8180–8182Publication Date (Print):November 1, 1973Publication History Published online1 May 2002Published inissue 1 November 1973https://doi.org/10.1021/ja00805a045RIGHTS & PERMISSIONSArticle Views74Altmetric-Citations21LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (417 KB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

Crystal structure of an acetylene sorption complex of zeolite 4A

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCrystal structure of an acetylene sorption complex of zeolite 4AAllen A. Amaro and Karl SeffCite this: J. Phys. Chem. 1973, 77, 7, 906–910Publication Date (Print):March 1, 1973Publication History Published online1 May 2002Published inissue 1 March 1973https://doi.org/10.1021/j100626a010RIGHTS & PERMISSIONSArticle Views165Altmetric-Citations37LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (764 KB) Get e-Alerts