MODIFIED BET EQUATION FOR SORPTION/DESORPTION ISOTHERMS

Abstract

As a result of modifications of BET model assumptions a new equation for sorption/desorption isotherms containing three constants was obtained. The proposed equation was verified successfully by means of measurements of sorption and desorption isotherms of water vapour for 29 substances and low-temperature adsorption of argon on 10 materials. Our own equation fits better, sometimes even much better, to the experimental points than the relations proposed by Harkins and Jura. Kühn, Halsey, Henderson, and Brunauer. Emmett and Teller (n = ∞).