Carbon Dioxide Capture by Modified UVM-7 Adsorbent

Abstract

In this study, bimodal meso-porous silica (UVM-7) synthesized and fabricated amino silane modified supports were characterized by powder X-ray diffraction (XRD), N2 adsorption/desorption, transmission electron microscope (TEM), elemental analysis and titration. Capacity of CO2 capture on modified bimodal pore structure silica at 70°C was calculated using breakthrough curves; and it was found that the modified UVM-7 captured more CO2 than unmodified UVM-7 and pore structure of UVM-7 make it suitable for loading large molecules such as tri-amino silanes. The adsorbents modified with tri-amino silane showed the largest capacity. Dynamic and kinetic of adsorption were investigated by mathematical models in order to prediction of adsorption behavior. Yoon Nelson model was successfully employed to describe the adsorption breakthrough curves of CO2 and Avrami model applied as a kinetic model and was in good agreement with experimental data in comparison with two other kinetic models including Lagergen's pseudo-first and pseudo-second order models.