Mesoporous carbon supported MgO for CO2 capture and separation of CO2/N2

Abstract

Mesoporous carbon derived from pongamia pinnata fruit hulls was used as support to incorporate magnesium oxide for the study of CO2 adsorption and separation of CO2/N2. All synthesized adsorbents were characterized by PXRD, N2 adsorption-desorption isotherms, Raman and SEM with EDX techniques. Characterization results revealed the existence of magnesium oxide on mesoporous carbon. CO2 adsorption on MgO incorporated mesoporous carbon was higher than bulk mesoporous carbon, due to the electrostatic interaction between magnesium oxide and CO2. High CO2 adsorption capacity 1.68 mmol/g was obtained for 10 wt% MgO incorporated mesoporous carbon at 298 K, 1 bar compared to remaining loadings, because of the high content of MgO. However, the N2 adsorption capacity decreased with the increase of MgO content due to a decrease in surface area and no interaction of the N2 molecule with the adsorbent. The selectivity of CO2/N2 was higher on 10 wt% MgO incorporated mesoporous carbon and the value was 40. The heat of CO2 adsorption was 36KJ/mol at low coverage of CO2, and CO2 adsorption capacity was constant in each adsorption cycle over the same adsorbent.