An investigation of the interaction of activated carbon and organic solvents by Inverse Gas and Liquid Chromatography

摘要

For many applications it is desirable to study the energy distribution for different adsorption sites (surface heterogeneity). In the case of activated carbon this is particularly useful for the understanding of changes in surface chemistry due to surface modification and activation processes. In this study an acidic and basic probe molecule (Dichloromethane and Ethyl acetate) are used to achieve a better understanding of the surface chemistry. IGC and ILC experiments are conducted for a comparison of the adsorption properties in the liquid and vapour phase. Experimental results from both techniques suggest a stronger interaction of F400 with the acidic probe molecule while the interaction with the basic adsorbate is quite similar for both activated carbons. This indicates a difference in the basic surface groups for the two carbons. The total values of the adsorption potentials are smaller for the ILC experiments, probably due to a non-negligible uptake of the mobile phase (hexane).