Roman Wojsz

An attempt at determination of the structural heterogeneity of microporous adsorbents

Abstract The general equation of the adsorption isotherm has been derived containing the parameter determining structural heterogeneity related to dimensions of micropores existing in microporous adsorbents. As opposed to the Stoeckli equation, our equation can be used for all microporous adsorbents.

Sorption of polar substances on active carbons

Abstract The mechanism of polar substances sorption on active carbons have been discussed using some aliphatic alcohols as an example. An effort has been undertaken to determine the role of both the specic adsorbate-adsorbent sorption and the adsorbate-adsorbate association in the total sorption of studied alcohols. It has been stated that, at small filling degrees, there is no consistence with the theory of volume filling of micropores because of the existence of both the association and the specific adsorbate-adsorbent interactions. An analysis of changes in fundamental thermodynamic functions has shown that, at great filling degrees, the fundamental assumptions of Dubinins theory can be realized.

Description of adsorption of polar substances on microporous adsorbents using the modified Polanyi-Dubinin potential theory

Abstract Mechanism of adsorption of lower aliphatic alcohols and amines on active carbon surfaces has been studied. Interpretation of the results required application of the modified Polanyi-Dubinin potential theory. A basic difference in adsorption of alcohols and amines has been found. Thus, the degree of alcohols association is lower in the adsorbed phase than in the liquid phase, whereas the reverse is observed for amines.

Adsorption of polar vapors by microporous carbon adsorbents

Abstract Applicability of the Polanyi-Dubinin potential theory to polar vapor adsorption on microporous carbon adsorbents has been evaluated. An isotherm equation which contains a parameter related to micropore size and which determines the structural heterogeneity of microporous adsorbents is generally the most useful.

Adsorption of associating and non-associating adsorbates on microporous carbon adsorbents

Abstract The adsorption of different chemical substances on microporous carbon adsorbents has been investigated. It has been determined that the chemical character of the molecules adsorbed as well as the adsorbent texture determine the adsorption kinetics. In the case of alcohols, one of the parameters determining the sorption mechanism is the formation of complexes. As was shown earlier, the rates of complex molecule formation for methyl and ethyl alcohols differ significantly.

Influence of microporous adsorbent texture and adsorbate type on the shape of the condensation distribution function

Abstract Equations of the distribution function of adsorption energy for adsorbents of heterogeneous micropores system have been derived with the condensation approximation method. The influences of adsorbent texture and adsorbate type on the shape of the function have been studied. As it has been stated, the maximum and the shape of the distribution function are decided by sizes of micropores and type of adsorbate used.

Distribution functions of structural heterogeneity of microporous adsorbents

The distribution functions of structural heterogeneity of microporous adsorbents have given. Influences of adsorbents and adsorbates types on this heterogeneity have been studied.ZusammenfassungEs werden Verteilungsfunktionen für die strukturelle Heterogenität von mikroporösen Adsorbentien angegeben. Die Einflüsse der Adsorbens- und Adsorbatarten auf diese Heterogenität wurden untersucht.

Porous texture of active carbons

Abstract The texture of prepared active carbons has been characterized using the adsorption and porosimetric measurements. The distribution curves approximately characterizing the micropores occurring in active carbons can be determined using the slit-like model for micropores. The share of micropores is dominating one independently on the method of active carbon preparation.

Functions defining capillary structure of microporous adsorbents

The applicability of earlier derived equations for adsorption isotherms for the determination of differential curves characterizing the approximate distribution of micropore volumes in relation to their radii is studied. It is concluded that besides the Gaussian distribution, the Rayleigh and exponential distributions also possess a physical sense.

An attempt to determine the function defining capillary structure of microporous adsorbents

Abstract An integral equation for the global isotherm of adsorption has been employed for the description of the adsorption process on microporous adsorbents of heterogeneous pores system. On this basis, the approximate curves characterizing the distribution of the volume of micropores in relation to their radii have been determined. It has been stated that the variability intervals of characteristic dimensions of pores depend on the type of adsorbate as well as on the adsorbate-adsorbent interaction.