Université de Neuchâtel

On the characterization of microporous carbons by immersion calorimetry alone

Stoeckli, Fritz ; Centeno, Teresa A.

In: Carbon, 1997, vol. 35, no. 8, p. 1097-1100

Immersion calorimetry is a useful tool for the characterization of solid surfaces in general, but in the case of microporous solids it usually requires complementary information, obtained from an adsorption isotherm. This article demonstrates the possibilities and the limitations of this technique when used alone. It appears that the use of a standard value for the enthalpy immersion does not...

Université de Neuchâtel

Dynamic adsorption of vapour mixtures in active carbon beds described by the Myers-Prausnitz and dubinin theories

Lavanchy, André ; Stoeckli, Fritz

In: Carbon, 1997, vol. 35, no. 10, p. 1573-1579

The adsorption of binary vapour mixtures from air by active carbon beds can be predicted with a good accuracy by adapting a model developed earlier for single vapours. This model is based on a semi-implicit finite difference scheme. Multiple adsorption of vapours is described by the combined theories of Myers-Prausnitz and of Dubinin (MPD), which have already been applied successfully to static...

Université de Neuchâtel

Recent developments in Dubinin's theory

Stoeckli, Fritz

In: Carbon, 1998, vol. 36, no. 4, p. 363-368

Dubinin's theory, developed in successive stages between 1947 and 1971 and extended to immersion calorimetry in the 1980s, has recently found new applications. It has been shown that water adsorption by microporous carbons, corresponding to type IV and V isotherms, can be described by the Dubinin-Astakhov (D-A) equation. The extension to immersion calorimetry is also valid and provides...

Université de Neuchâtel

Dynamic adsorption, in active carbon beds, of vapour mixtures corresponding to miscible and immiscible liquids

Lavanchy, André ; Stoeckli, Fritz

In: Carbon, 1999, vol. 37, no. 2, p. 315-321

It is shown that the combined Myers–Prausnitz–Dubinin theory (MPD) can be extended to the adsorption of ternary mixtures from an air stream. When combined with a computer model developed for dynamic adsorption, it provides a satisfactory agreement with the experimental breakthrough curves in active carbon beds. On the other hand, as illustrated by a mixture of water and 2-chloropropane...

Université de Neuchâtel

On the use of standard DRK isotherms in Dubinin’s t/F method

Hugi-Cleary, Deirdre ; Stoeckli, Fritz

In: Carbon, 2000, vol. 38, no. 9, p. 1309-1313

It is shown that the adsorption of benzene, carbon tetrachloride, dichloromethane and nitrogen by a typical non-porous carbon black follows the Dubinin–Radushkevich–Kaganer equation. The requirement for temperature invariance is fulfilled, with an average characteristic energy Eo=10.8 kJ mol−1. This expression is compared with the standard isotherms for benzene and...

Université de Neuchâtel

Water adsorption by activated carbons in relation to their microporous structure

Slasli, Abdou ; Jorge, M. ; Stoeckli, Fritz ; Seaton, N. A.

In: Carbon, 2003, vol. 41, no. 3, p. 479-486

The present paper examines the adsorption of water by microporous carbons in the absence of specific interactions. The modelling of water adsorption for 293 and 310 K, using variable pore size distributions (PSD), shows that the type V isotherms follow the Dubinin–Astakhov (DA) equation and fulfill the requirement for temperature invariance. Furthermore, the parameters of the DA equation can be...