Mesoporous silica SBA-15 samples with and without controlled framework microporosity were prepared and used directly or impregnated with polymer amine as adsorbent for CO 2. These samples were evaluated for their ability to adsorb CO 2 by obtaining their equilibrium adsorption isotherms using volumetric adsorption at three different temperatures of 273K, 278K and 283K. The data obtained were analyzed using Freundlich adsorption isotherm model while the isosteric heats of adsorption were estimated by the Clausius-Clapeyron equation. Under comparable conditions, the adsorption performance of silica SBA-15 was found to be strongly dependent upon the framework microporosity. However, the microporosity contribution to CO 2 adsorption in amine-modified SBA-15 was not obvious as amine blocked micropores and dominated CO 2 adsorption. The SBA-15 sample with higher microporosity displayed higher CO 2 uptake and the CO 2 uptake by amine-modified SBA-15 samples correlated with their total surface areas, as expected. These findings revealed the importance of surface area in designing an adsorbent for CO 2..
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Surfaces, Coatings and Films
- Colloid and Surface Chemistry