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

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1205
Author(s):  
Alejandro Orsikowsky-Sanchez ◽  
Christine Franke ◽  
Alexander Sachse ◽  
Eric Ferrage ◽  
Sabine Petit ◽  
...  

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.

2017 ◽  
Vol 5 (5) ◽  
pp. 2110-2114 ◽  
Author(s):  
G. R. Berdiyorov ◽  
M. Neek-Amal ◽  
I. A. Hussein ◽  
M. E. Madjet ◽  
F. M. Peeters

Density functional theory calculations are used to study gas adsorption properties of a recently synthesized CaO monolayer. Due to its topology and strong interaction with the CO2 molecules, this material possesses a remarkably high CO2 uptake capacity and is highly selective towards CO2 against other major greenhouse gases.


2021 ◽  
pp. 114436
Author(s):  
Chengrui Wang ◽  
Yanhong Fang ◽  
Huamei Duan ◽  
Guangfen Liang ◽  
Wanying Li ◽  
...  

2011 ◽  
Vol 115 (26) ◽  
pp. 12873-12882 ◽  
Author(s):  
Shiyou Hao ◽  
Hong Chang ◽  
Qiang Xiao ◽  
Yijun Zhong ◽  
Weidong Zhu

2013 ◽  
Vol 66 (23) ◽  
pp. 4093-4106 ◽  
Author(s):  
Mürsel Arici ◽  
Okan Zafer Yeşılel ◽  
Seda Keskın ◽  
Onur Şahın ◽  
Orhan Büyükgüngör

2015 ◽  
Vol 44 (7) ◽  
pp. 1004-1006
Author(s):  
Takahito Mitome ◽  
Yoshiaki Uchida ◽  
Norikazu Nishiyama

2021 ◽  
pp. 107135
Author(s):  
Khang D. Pham ◽  
Pham Cong Dinh ◽  
Do Van Diep ◽  
Tuan V. Vu ◽  
Hai L. Luong ◽  
...  

2019 ◽  
Author(s):  
Jonathan Carney ◽  
David Roundy ◽  
Cory M. Simon

Metal-organic frameworks (MOFs) are modular and adjustable nano-porous materials with applications in gas storage, separations, and sensing. Flexible/dynamic components that respond to adsorbed gas can give MOFs unique or enhanced adsorption properties. Here, we explore the adsorption properties that could be imparted to a MOF by a rotaxane molecular shuttle (RMS) in its pores. In an RMS-MOF, a macrocyclic wheel is mechanically interlocked with a strut. The wheel shuttles between stations on the strut that are also gas adsorption sites. We pose and analyze a simple statistical thermodynamic model of gas adsorption in an RMS-MOF that accounts for (i) wheel/gas competition for sites on the strut and (ii) the entropy endowed by the shuttling wheel. We determine how the amount of gas adsorbed, position of the wheel, and energy change upon adsorption depend on temperature, pressure, and the interactions of the gas/wheel with the stations. Our model reveals that, compared to an ordinary Langmuir material, the chemistry of the RMS-MOF can be tuned to render adsorption more or less temperature-sensitive and release more or less heat upon adsorption. The model also uncovers a non-monotonic relationship between temperature and the position of the wheel if gas out-competes the wheel for its preferable station.


2020 ◽  
Author(s):  
Jonathan Carney ◽  
David Roundy ◽  
Cory M. Simon

Metal-organic frameworks (MOFs) are modular and tunable nano-porous materials with applications in gas storage, separations, and sensing. Flexible/dynamic components that respond to adsorbed gas can give MOFs unique or enhanced adsorption properties. Here, we explore the adsorption properties that could be imparted to a MOF by a rotaxane molecular shuttle (RMS) in its pores. In the unit cell of an RMS-MOF, a macrocyclic wheel is mechanically interlocked with a strut of the MOF scaffold. The wheel shuttles between stations on the strut that are also gas adsorption sites. At a level of abstraction similar to the seminal Langmuir adsorption model, we pose and analyze a simple statistical mechanical model of gas adsorption in an RMS-MOF that accounts for (i) wheel/gas competition for sites on the strut and (ii) gas-induced changes in the configurational entropy of the shuttling wheel. We determine how the amount of gas adsorbed, position of the wheel, and differential energy of adsorption depend on temperature, pressure, and the interactions of the gas/wheel with the stations. Our model reveals that, compared to a rigid, Langmuir material, the chemistry of the RMS-MOF can be tuned to render gas adsorption more or less temperature-sensitive and to release more or less heat upon adsorption. The model also uncovers a non-monotonic relationship between the temperature and the position of the wheel if gas out-competes the wheel for its preferable station.


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