Vapor adsorption and liquid immersion experiments on carbon molecular sieves

Abstract

The adsorption and immersion of different fluids on a series of carbon molecular sieves was investigated. The carbon adsorbents with significantly different micro- and mesoporosity were characterized by means of nitrogen and argon adsorption at cryogenic temperatures, vapor adsorption at 298.15 K, liquid-immersion enthalpy and pH value measurements. The polarity and chain length of the fluid molecules used for adsorption and immersion were varied to study the texture and surface polarity, the accessibility of the pore systems and the adsorption mechanisms in micro- and mesoporous adsorbents. The experimental data are evaluated with regard to correlations between adsorption and immersion measurements. The obtained results affirm once again that vapor-sorption and liquid-immersion experiments extend the characterization tool for hierarchical materials in a meaningful manner.