| Strong evidence exists that anthropogenic emissions of CO2 have contributed significantly to global climate change. Therefore, it is essential to mitigate anthropogenic CO2 emissions. Unfortunately, current technology for CO2 capture relying on amine scrubbing is costly because of the energy requirements for amine regeneration. Accordingly, alternative CO2 capture technologies are sought. Among these, the use of solid adsorbents appears most promising in reducing the cost of CO 2 capture.;This project focused on the development of amine-based solid sorbents with a low CO2 desorption activation energy and a high CO 2 sorption capacity. Three different porous materials including nanoporous titanium oxyhydrate (TiO(OH)2), modified carbon nanotubes (MCNTs), and poly(divinylbenzene/2-ethylhexyl methacrylate) (polyHIPE) have been prepared as adsorbent supports. The first two CO2 adsorbents were prepared by immobilizing tetraethylenepentamine (TEPA) onto TiO(OH)2 and MCNTs resulting in TiO(OH)2/TEPA and MCNTs/TEPA adsorbents. Polyethylenimine (PEI) was used to prepare a polyHIPE/PEI adsorbent through impregnation.;TiO(OH)2/TEPA was used as an adsorbent for the removal of CO2 at a low concentration (1 vol.% CO2 in N2). At optimal conditions, the CO2 sorption capacity reached 3.1 mmol CO 2/g-sorbent at 60 °C. It was observed that the activation energies for CO2 adsorption and desorption of TiO(OH)2/TEPA are 19.6 kJ/mol and 51.1 kJ/mol, respectively. This low CO2 desorption activation energy can contribute to a lower CO2 capture cost.;MCNTs/TEPA and polyHIPE/PEI adsorbents were also evaluated for CO 2 capture using 10 vol.% CO2 in N2. At the optimal conditions CO2 sorption capacity reached 5 mmol CO2/g-sorbent with MCNTs/TEPA and 4 mmol CO2/g-sorbent with polyHIPE/PEI. Kinetic and thermodynamic adsorption/desorption studies found activation energies for CO2 desorption are 39.9 kJ/mol for MCNTs/TEPA and 36.12 kJ/mol for polyHIPE/PEI.;The low activation energies for CO2 desorption using the prepared adsorbents can contribute to a lower CO2 capture cost. Therefore, the prepared adsorbents have potential for application to CO2 capture from gas mixtures. |
