３パラメター吸着式の誘導とその適応性 ＩＩＩ 微小径空孔を持つカーボンブラックへの吸着等温線に対する３パラメター吸着式の適応性

Abstract

The accomodation of a three-Parameter adsorption equation derived on the basis of statistical thermodynamics in the model of localized adsorption for monolayer and non-localized adsorption for the upper adphase over the 1st layer to the experimental adsorption isotherms has been investigated by N2 adsorption isotherms on carbon black with a micropore which is preadsorbed by nonane. The three-parameter adsorption equation agreed well with experimental isotherms in the range of relative pressure from 0.01 to 0.6. These had wider range of agreement than with the BET equation i. e., in a range from 0.05 to 0.2. Accordingly, the upper adphase over the monolayer for the formation in an intermediate relative pressure range after the completion of the monolayer was perceived not to form stacked layers like the localized multilayer proposed by BET theory, but to form preferably a non-localized mobile adphase. The surface areas obtained from the three-parameter adsorption equation, a Huttigtype adsorption equation and BET equation, agreed with each others within 15%, respectively. These surface areas were investigated by comparison of the results from αs-plots of these experimental isotherms. Since the surface areas obtained from the isotherms in the reduction of the micropore amount from αs-plot in the application of each adsorption equations agreed with the outer plane surface areas from the slope of the linear portion in αs-plots, the micropores would be filled up in an extremely low relative pressure range. The surface areas obtained from the three-parameter adsorption equation was perceived to be reasonable.