Pore geometry and isosteric heat: an analysis of carbon dioxide adsorption on activated carbon

Abstract

The isosteric heat of carbon dioxide adsorption on activated carbon is determined by grand canonical Monte Carlo simulations. The results, obtained at room temperature and low pressure for an adsorbent model with slit-type porosity, show that the isosteric heat depends strongly on the slit width. The maximum of the isosteric heat is attained for a pore width such that cooperative effects between the adsorbed molecules enhance the adsorption. The possibility of estimating the isosteric heat of a macroscopic sample, from adsorption isotherms computed for a distribution of slit pores of given sizes, is discussed.

Keywords:

• adsorption
• isosteric heat