CO₂ adsorption on amine-functionalized periodic mesoporous benzenesilicas.
CO2 adsorption was investigated on amine-functionalized mesoporous silica (SBA-15) and periodic mesoporous organosilica (PMO) samples. Hexagonally (p6mm) ordered mesoporous SBA-15 and benzene-PMO (BPMO) samples were prepared in the presence of Pluronic P123 block copolymer template under acidic conditions. Three kinds of amine-containing organosilanes and polyethylenimine were used to functionalize SBA-15 and BPMO. Small-angle X-ray scattering and nitrogen adsorption isotherms showed that these samples featured ordered mesostructure, high surface area, and narrow pore size distributions. Solid-state (13)C- and (29)Si cross-polarization magic-angle spinning NMR spectra showed chemical linkage between amine-containing modifiers and the surface of mesoporous materials. The chemically linked amine-containing modifiers were found to be on both the inner and outer surfaces. N-[3-(trimethoxysilyl)propyl]ethylenediamine-modified BPMO (A2-BPMO) sample exhibited the highest CO2 uptake (i.e., ∼3.03 mmol/g measured on a volumetric adsorption analyzer) and the fastest adsorption rate (i.e., ∼13 min to attain 90% of the maximum amount) among all the samples studied. Selectivity and reproducibility measurements for the A2-BPMO sample showed quite good performance in flowing N2 gas at 40 mL/min and CO2 gas of 60 mL/min at 25 °C.
†Department of Fine Chemistry, Seoul National University of Science and Technology, Seoul 139-743, Korea.
Kyohyun
K
Sim
†Department of Fine Chemistry, Seoul National University of Science and Technology, Seoul 139-743, Korea.
Nakwon
N
Lee
†Department of Fine Chemistry, Seoul National University of Science and Technology, Seoul 139-743, Korea.
Joonseok
J
Kim
†Department of Fine Chemistry, Seoul National University of Science and Technology, Seoul 139-743, Korea.
Eun-Bum
EB
Cho
‡Department of Chemistry and Biochemistry, Kent State University, Kent, Ohio 44242, United States.
Chamila
C
Gunathilake
‡Department of Chemistry and Biochemistry, Kent State University, Kent, Ohio 44242, United States.
Mietek
M
Jaroniec
CO2 adsorption; N-[3-(trimethoxysilyl)propyl]ethylenediamine; periodic mesoporous organosilica; polyethylenimine