(338v) CO2 Capture Using Highly Selective Amine-Bearing Mesoporous Silica | AIChE

(338v) CO2 Capture Using Highly Selective Amine-Bearing Mesoporous Silica


Belmabkhout, Y. - Presenter, University of Ottawa
Sayari, A. - Presenter, University of Ottawa

Although the transition towards a more sustainable energy economy is urgent, fossil fuels, which are believed to be the main contributor to global warming, are likely to remain the main source of energy supply for the foreseeable future. The total greenhouse gas (GHG) emission in the world increased considerably; mostly due to the energy industries and transportation sector (Marland et al., 2006). Therefore, separation, and ultimately sequestration of CO2 in fossil-fuel power plants stack gas and other industrial gases is required to mitigate global warming.

Among the strategies for CO2 separation, gas absorption using alkaloamine solutions is the most common technology used for large scale operations. However, this method is highly energy intensive. Compared to other separation technologies, adsorption is recognized to be an economically attractive candidate to complement or substitute absorption-based processes due to its lower energy requirements (Aaron and Tsouris, 2005). Adsorption may also be suitable for the separation of pure CO2 which could be pressurized and ultimately stored.

In addition to low cost, the ideal medium for CO2 adsorption should combine the following properties (i) high CO2 dynamic adsorption capacity (ii) high CO2 selectivity, and (iii) high stability to prolonged adsorption-regeneration cycling. Inspired by the amine absorption technology, our group developed solid-supported amine adsorbents (Harlick and Sayari, 2007; Belmabkhout and Sayari, 2009; Serna-Guerrro et al., 2008) for CO2 separation and purification. The gas-solid approach is expected to combine the high selectivity and reversibility of the CO2-amine chemistry and the low energy requirements to regenerate the solid adsorbent.

In this work, adsorption of CO2 and N2, the main components of flue gas, was investigated at ambient temperature and up to 20 bar on triamine surface-modified pore expanded-MCM-41 silica (TRI-PE-MCM-41). The adsorption isotherms obtained showed much higher CO2 adsorption capacity in comparison to N2 over all the range of pressure. Column breakthrough measurements using CO2/N2 mixture showed almost infinite selectivity of CO2 over N2. The effect of impurities in flue gas such as O2 and water was also investigated. Our findings clearly demonstrate that TRI-PE-MCM-41 is a promising material for the removal of CO2 from flue gas.


Aaron, D. and C. Tsouris (2005). Separation of CO2 from flue gas: a review. Sep. Sci. Technol., 40, 321-348.

Belmabkhout, Y. and A. Sayari (2009). Effect of pore expansion and amine functionalization of mesoporous silica on CO2 adsorption over a wide range of pressure and temperature. Adsorption, in press.

Harlick, P.J.E. and A. Sayari (2007). Applications of pore-expanded mesoporous silica. 5. Triamine grafted material with exceptional CO2 dynamic and equilibrium adsorption performance. Ind. Eng. Chem. Res., 46, 446-458.

Marland, J., T.A. Boden and R.J. Andres (2006). Regional and national CO2 emissions. In: Trends: A Compendium of Data on Global Climate Change; Carbon Dioxide Information Analysis Center, U.S. Department of Energy, http://cdiac.ornl.gov/.

Serna-Guerrero, R., E. Da'na and A. Sayari (2008). New insights into the interactions of CO2 over amine-functionalized silica, Ind. Eng. Chem. Res., 47, 9406-9412.