Investigation of Non-Thermodynamical CO2 Adsorption Behavior for Amine-Modified Nanoporous Silica ()
ABSTRACT
Non-thermodynamical CO2 adsorption behavior for amine-modified nanoporous silica is clarified by evaluating the mobility of organic functional
group inside mesopores by using pulsed NMR technique. CO2 adsorption
behavior of nanoporous silica modified with amino-propyl silane (AP) changes significantly
depending on the amount of AP loaded. A low AP loaded sample shows normal
adsorption behavior; the amount of CO2 adsorbed decreases with
increasing temperature. In contrast, a high AP loaded sample possesses
non-thermodynamic CO2 adsorption behavior in which the amount of CO2 adsorbed increases with increasing temperature in within a certain temperature
range. To address the mechanism, a pulsed NMR technique was employed to clarify
the mobility of AP molecules, and it was found that the mobility of mobile
components in a high AP loaded sample increased drastically with increasing temperature
while the mobility in a low AP loaded sample remained unchanged. It is
understood that the enhancement of the diffusion of CO2 inside nanopores
leads to the non-thermodynamic adsorption behavior.
Share and Cite:
Yano, K. , Setoyama, N. and Fukumori, K. (2020) Investigation of Non-Thermodynamical CO
2 Adsorption Behavior for Amine-Modified Nanoporous Silica.
Advances in Materials Physics and Chemistry,
10, 53-62. doi:
10.4236/ampc.2020.103005.