Microporous carbons simulated

A morphological model for microporous carbons has recently been reported [32] in which rigid aromatic sheets of sp- bonded carbon are randomly placed in a three-dimensional cubic simulation cell with periodic boundaries. A typical carbon plate has the structure shown in Fig, 3a, The plates are roughly aligned in the simulation cell, as illustrated in Fig, 3b, but with random variations in their angles of tilt. RMC simulation is carried out by sampling three types of changes to the carbon structure (i) translation and... 

The adsorption of gas mixtures has been extensively studied. For example, Wendland et al. [64] applied the Bom—Green—Yvon approach using a coarse grained density to study the adsorption of subcritical Lennard-Jones fluids. In a subsequent paper, they tested their equations with simulated adsorption isotherms of several model mixtures [65]. They compared the adsorption of model gases with an equal molecular size but different adsorption potentials. They discussed the stmcture of the adsorbed phase, adsorption isotherms, and selectivity curves. Based on the vacancy solution theory [66], Nguyen and Do [67] developed a new technique for predicting the multicomponent adsorption equihbria of supercritical fluids in microporous carbons. They concluded that the degree of adsorption enhancement, due to the proximity of the pore... 

Aukett PN, Quirke N, Riddifird S, Tennison SR. Methane adsorption on microporous carbons -comparison of experiment, theory, and simulation. Carbon 1992 30(6) 913-924. 

Perez-Mendoza M, Schumacher C, Suarez-Garcfa F, Almazan-Almazan MC, Domingo-Garcia M, Lopez-Garzon FJ, and Seaton NA. Analysis of the microporous texture of a glassy carbon by adsorption measurements and Monte Carlo simulation. Evolution with chemical and physical activation. Carbon, 2006 44(4) 638-645. 

Because of its diatomic nature and permanent quadrupole moment, the physisorp-tion of nitrogen at 77 K presents special problems. The application of DFT is facilitated if the molecules are assumed to be spherical, which was the approach originally adopted by Seaton et al. (1989) and also by Lastoskie et al. (1993). The analytical procedures already outlined in Chapter 7 (Section 7.6) do not depend on the meniscus curvature and are in principle applicable to both capillary condensation and micropore filling. The non-local version of the mean field theory (NLDFT), which was used by Lastoskie, gave excellent agreement with computer simulation when applied to the carbon slit pore model. However, as pointed out earlier, these computational procedures are not entirely independent since they involve the same model parameters. 

Recent research activities on nanoporous materials have stimulated fundamental studies on adsorption mechanism in micropores [1 5]. Both of the precise measurement of high resolution adsorption isotherms from the low P/Po region and molecular simulation showed the presence of monolayer adsorption on the micropore walls and further filling in the residual spaces after monolayer completion for supermicropores (0.7 nm < pore width w <2 nm) the contribution by the monolayer to the filling in the residual spaces is comparable to that by the pore walls [6-10]. Systematic researches on activated carbon fiber (ACF) having slit-shaped micropores[l 1,12] have contributed to elucidation of the mechanism of micropore filling to develop better adsorbents in adsorption and separation engineering. 

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