A macroporous organic adsorbent was
designed and prepared using
the template method, with acrylamide (AM) as the skeleton, glycidyl
methacrylate (GMA) as the shell, and F-127 and Pluronic block copolymer
(P123) as surfactants, and grafted with polyethyleneimine (PEI). Solid
adsorbents were used for carbon dioxide capture. The effect of the
AM/GMA mass ratio on the spherical morphology, through-hole structure,
specific surface area, hardness, hydrophobicity, and thermal stability
was comprehensively investigated, and the CO2 adsorption
performance of the PEI-modified adsorbent was studied. Surface area
and morphology characterization showed that after the introduction
of GMA, the wall thickness and roughness increased, and the specific
surface area and the mass of GMA first showed a positive correlation
and then a negative correlation. In addition, the thermal stability
was slightly reduced, and the hydrophobicity was greatly improved.
The CO2 adsorption results revealed that the organic adsorbents
exhibited higher adsorption capacity and faster adsorption kinetics
than conventional CO2 capture materials, and their simple
synthesis enables their industrial application. The study revealed
that the preparation of PEI-modified adsorbents with a core–shell
structure greatly improved thermal stability and selectivity. When
the PEI loading was 50 wt %, the CO2 capacity of the core–shell
microspheres reached 3.11 mmol·g–1 at 40 °C,
and desorption can be completed at 85 °C. The proposed material
has a good industrial application prospect and shows an excellent
lifetime performance.