Studies of the Polar and Apolar Liquid Film Properties of Pure and Modified Activated Carbons by Thermal Analysis and Sorptiometric Methods

Abstract

Thermal analysis was used to investigate the adsorbed water layers and surface properties of various pure and modified commercial activated carbons. In addition, the thermodesorption of n-butanol, n-octane and benzene from samples saturated in a vacuum desiccator was studied under quasi-isothermal conditions. The mass loss Q-TG and differential mass loss Q-DTG curves obtained consisted of steps and inflections which were associated with the mechanism of wetting, adsorption and porosity properties of the studied surfaces. Adsorption/desorption isotherms of nitrogen on the activated carbon samples were measured using a sorptiomatic method. The specific surface areas, pore sizes, pore volumes and pore-size distribution functions have been calculated for the various samples. A correlation between the porosity parameters obtained from thermogravimetric and sorptiometric methods is presented.