Combining the advantages of high selectivity of amine groups

high capacity of microporous zeolite

and high transportation of mesoporous structures

amine modified micro/mesoporous composites may exhibit promising CO2 adsorption capability. In this study

a full-atomic mimetic amine modified micro/mesoporous composite of AM-5A-MCM-41 was constructed. CO2 adsorption and separation performance on AM-5A- MCM-41 composite were investigated by the grand canonical Monte Carlo (GCMC)

in which a specific combining rule was used to describe the weak chemical interaction between CO2 molecule and amine group. The simulation results demonstrate that CO2 is preferentially adsorbed around amine groups

which is grafted at the surface of mesoporous channels; and the CO2 adsorption capacity and its isosteric heat are greatly improved on AM-5A-MCM-41

whereas those of N2 are almost kept unchanged. For the separation of mixed gas of CO2 and N2

both CO2 adsorption capacity and CO2/N2 selectivity are greatly improved

due to the enhanced interaction between CO2 molecules and amine groups. The chemisorption plays a significant role in the capture of CO2 at low pressures and high temperature

giving a selectivity as high as 87.0 at 573 K and 100 kPa. The overall results show that molecular simulations serve as a powerful implement to assist the design and development of new promising CO2 adsorbents

highlighting the importance of this approach.