Hierarchical porous graphene-based carbons prepared by carbon dioxide activation and their gas adsorption properties

Covalent organic Imine polymers with intrinsic meso-porosity were synthesized by condensation reaction between 4,4-diamino diphenyl methane and (para/meta/ortho)-phthaladehyde. Even though these polymers were synthesized from precursors of bis-bis covalent link mode, the bulk materials were micrometer size particles with intrinsic mesoporous enables nitrogen as well as carbon dioxide adsorption in the void spaces. These polymers were showed stability up to 260o centigrade. Nitrogen gas adsorption capacity up to 250 cc/g in the ambient pressure was observed with type III adsorption characteristic nature. Carbon dioxide adsorption experiments reveal the possible terminal amine functional group to carbamate with CO2 gas molecule to the polymers. One of the imine polymers, COP-3 showed more carbon dioxide sorption capacity and isosteric heat of adsorption (Qst) than COP-1 and COP-2 at 273 K even though COP-3 had lower porosity for nitrogen gas than COP-1 and COP-2. We explained the trends in gas adsorption capacities and Qst values as a consequence of the intra molecular interactions confirmed by Density Functional Theory computational experiments on small molecular fragments.

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Synthesis of N-doped hierarchical porous carbon with excellent toluene adsorption properties and its activation mechanism

Environmental Pollution ◽

10.1016/j.envpol.2021.117113 ◽

2021 ◽

Vol 284 ◽

pp. 117113

Author(s):

Shengyong Lu ◽

Xinlei Huang ◽

Minghui Tang ◽

Yaqi Peng ◽

Shuchao Wang ◽

...

Keyword(s):

Porous Carbon ◽

Adsorption Properties ◽

Activation Mechanism ◽

Hierarchical Porous Carbon ◽

Hierarchical Porous

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Gas Porosimetry by Gas Adsorption as an Efficient Tool for the Assessment of the Shaping Effect in Commercial Zeolites

Nanomaterials ◽

10.3390/nano11051205 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1205

Author(s):

Alejandro Orsikowsky-Sanchez ◽

Christine Franke ◽

Alexander Sachse ◽

Eric Ferrage ◽

Sabine Petit ◽

...

Keyword(s):

Ir Spectroscopy ◽

Strong Interaction ◽

Gas Adsorption ◽

Co2 Adsorption ◽

Adsorption Properties ◽

Preparation Process ◽

Pore Filling ◽

Irreversible Adsorption ◽

Efficient Tool ◽

4A Zeolite

A set of three commercial zeolites (13X, 5A, and 4A) of two distinct shapes have been characterized: (i) pure zeolite powders and (ii) extruded spherical beads composed of pure zeolite powders and an unknown amount of binder used during their preparation process. The coupling of gas porosimetry experiments using argon at 87 K and CO2 at 273 K allowed determining both the amount of the binder and its effect on adsorption properties. It was evidenced that the beads contain approximately 25 wt% of binder. Moreover, from CO2 adsorption experiments at 273 K, it could be inferred that the binder present in both 13X and 5A zeolites does not interact with the probe molecule. However, for the 4A zeolite, pore filling pressures were shifted and strong interaction with CO2 was observed leading to irreversible adsorption of the probe. These results have been compared to XRD, IR spectroscopy, and ICP-AES analysis. The effect of the binder in shaped zeolite bodies can thus have a crucial impact on applications in adsorption and catalysis.

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Carbon Capture Performance of Amino-Modified MIL-101 at Room Temperature

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.395-396.637 ◽

2013 ◽

Vol 395-396 ◽

pp. 637-640

Author(s):

Yi Yang ◽

Zheng Ping Wang ◽

Ling Meng ◽

Lian Jun Wang

Keyword(s):

Carbon Dioxide ◽

Specific Surface ◽

Pore Structure ◽

Carbon Capture ◽

Room Temperature ◽

Ambient Pressure ◽

Metal Organic Framework ◽

Adsorption Properties ◽

Carbon Dioxide Adsorption ◽

Before And After

MIL-101, a metal-organic framework material, was synthesized by the high-temperature hydrothermal method. Triethylenetetramine (TETA) modification enabled the effective grafting of an amino group onto the surface of the materials and their pore structure. The crystal structure, micromorphology, specific surface area, and pore structure of the samples before and after modification were analyzed with an X-ray diffractometer, scanning electron microscope, specific surface and aperture tester, and infrared spectrometer. The carbon dioxide adsorption properties of the samples were determined by a thermal analyzer before and after TETA modification. Results show that moderate amino modification can effectively improve the microporous structure of MIL-101 and its carbon dioxide adsorption properties. After modification, the capacity of MIL-101 to adsorb carbon dioxide decreased only by 0.61 wt%, and a high adsorption capacity of 9.45 wt% was maintained after six cycles of adsorption testing at room temperature and ambient pressure.

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