Evaluation of Adsorption Property of Porous Carbon Materials (I) Evaluation by Benzene Adsorption in Vapor Phase

Abstract

A method is presented for evaluating the adsorption property of porous carbon materials in gas and liquid phases.Adsorption isotherms of benzene are determined on 19 kinds of activated carbons and the adsorption constants, W°and B, in Dubinin-Radushkevich equation are calculated.An adsorption equation is presented for predicting the adsorption isotherms of various organic compounds from aqueous solution.The equation, which is based on the multiple linear regression analysis, comprises four parameters: molecular refraction (M_r), number of hydrophilic group (N_f), micropore volume (W°), and function of pore volume distribution (B).Mr of adsorbate offers a basis for expressing quantitatively the adsorbentadsorbate interactions associated.with the dispersion forces.Nf in an adsorbate molecule is assumed to represent the strength of the adsorbate-water interactions.W°and B represent the adsorption capacity and the strength of adsorbent-adsorbate interaction, respectively. Another equation, in which the amounts of benzene adsorbed at P/P₀= 0.01 and 0.1 are used instead of W° and B, is presented and the method using the equation is very simple and useful for evaluating the adsorption property in gas and liquid phases.