Heat Capacity and Heat of Adsorption of Argon Adsorbed on Graphon

The interplay between molecular layering and clustering in adsorption of gases on graphitized thermal carbon black – Spill-over phenomenon and the important role of strong sites

“…The heat of adsorption at zero loading of 17.6kJ/mol can be compared with its value on a highly graphitized carbon black of 8.8kJ/mol (in good agreement with the theoretical calculation of 9kJ/mol; Do et al, 2008) and accords closely with the expected doubling in the heat of adsorption in slit pores that can accommodate one layer of molecules (Everett and Powl, 1976). Beebe et al, 1953Beebe et al, , 1954Pace et al, 1957Pace et al, , 1959; (b) Evolution of nitrogen isotherms at 77K for Spheron 6 with the graphitization temperature (data taken from Polley et al, 1953).…”

“…Polley et al (1953) demonstrated the evolution of the isotherms with the degree of graphitization; their isotherms ( Figure 3b) show the development of waves with increasing graphitization which approach the stepped (Type VI) isotherms found on exfoliated graphite and attributed to discrete adsorbate layer formation. The corresponding isosteric heat curves, shown in Figure 3a, have a decaying oscillating pattern, which again is typical for simple gases on a homogeneous surface co-workers, 1953, 1954;Bobka et al (1957); Pace et al (1960); Ross and Pultz, 1958) except at very low loadings where the presence of very small quantities of very strong sites (ultra-micropores) affects the heat. The isosteric heat at zero loading for the basal plane can be obtained by extrapolating the linear section in the sub-monolayer region to zero loading, and it is a measure of the intrinsic interaction between an adsorbate molecule and the graphene basal planes.…”

On the isosteric heat of adsorption of non-polar and polar fluids on highly graphitized carbon black

“…Argon and nitrogen adsorptions on graphite are perhaps the most widely studied systems in the literature, where reliable isotherms and isosteric heats can be found [2][3][4][5][19][20][21][22][23][24][25]. Fig.…”

Effects of surface mediation on the adsorption isotherm and heat of adsorption of argon on graphitized thermal carbon black

“…Experimental isosteric heats of argon on GTCB at 77 K are available in the literature, for example, Beebe et al [20,21], Grillet et al [18]. Bobka et al [22], Pace and Siebert [23], and Avgul and Kiselev [19]. Among these data, only the data of Grillet et al has high enough resolution to reveal the heat spike in the isosteric heat curve versus loading.…”