Carbon dioxide adsorption on the microporous ACC carbon adsorbent

Abstract

Adsorption isotherms of carbon dioxide on the microporous ACC carbon adsorbent and the adsorption deformation of the adsorbent were measured. The heats of adsorption at tempera tures raising from 243 to 393 K and pressures from 1 to 5•10 6 Pa were measured. In the low temperature region (243 K), an increase in the amount adsorbed is accompanied by adsorbent contraction, and at high micropore fillings (а > 10 mmol g -1 ) the ACC carbon adsorbent expands. At high temperatures, adsorbent expansion is observed in the whole region of micropore filling. At 243 K in the low filling region (а < 1 mmol g -1 ), the heat of adsorption decreases smoothly from 27 to 24 kJ mol -1 . The heat of adsorption remains virtually unchanged in the interval 2 mmol g -1 < а < 11 mmol g -1 and then decreases to 8 kJ mol -1 at а = 12 mmol g -1 .Taking into account the nonideal character of the gas phase and adsorbent deformation the heats of adsorption are strongly temperature dependent in a region of high pressures.

Adsorption-induced deformation of nanoporous materials—A review

“…In such a formulation, the chemical potential of the strained surface becomes a function of porosity itself. The authors proposed an iterative scheme to solve the coupled problem and their calculations agreed well with the experimental data on CO 2 adsorption on activated carbon at three different temperatures from Yakovlev et al 155 Vandamme et al 156 augmented the conventional poromechanics equations with surface stress terms to get predictions of the strain of the porous medium due to the change of the surface stress. In their formulation, it was assumed that the surface stress is changing according to the Gibbs adsorption equation, i.e., in the same way as the surface energy does.…”

Solvation forces between molecularly rough surfaces

“…With the further increase of adsorption, the packing is densified and the hard-core repulsion interaction become dominant that lead to the increase of the solvation pressure. This behavior is typical for microporous carbon [49,50] and other microporous materials like zeolites [50][51][52].…”

Solid deformation induced by the adsorption of methane and methanol under sub- and supercritical conditions

“…This early work was followed by experimental studies of the swelling of charcoal that accompanies the adsorption of water, carbon dioxide and other gases by Bangham and Fakhoury [2] and several investigations of the extension of carbon rods under the influence of a variety of organic vapours by Canadian groups [3][4][5]. More recent experimental work on the deformation of carbons during the adsorption of different gases has been reported by Fomkin and co-workers [6][7][8] and a dilatometric investigation of the deformation of carbon xerogels has been made by Balzer and co-workers [9] who concluded that micropores in the adsorbents made the most significant contribution to the expansion and contraction of these materials. Recognizing the significance of the effect of adsorption-induced deformation, more attention is paid on this phenomenon for various systems beside carbonaceous materials, such as porous glass [10], zeolites [11], silica gels [12], porous silicon [13,14] and metal-organic frameworks (MOFs) [15,16].…”