Synthesis and CO2 Adsorption Properties of Molecularly Imprinted Adsorbents

A series of molecularly imprinted adsorbents of CO2 were developed by molecular self-assembly procedures, using ethanedioic acid, acrylamide, and ethylene glycol dimethacrylate as template, functional monomer, and cross-linker, respectively. Textural properties of these adsorbents were characterized by N-2 adsorption experiment, thermo-gravimetric analysis, and Fourier transform infrared spectroscopy. CO2 adsorption capacities of adsorbents were investigated by thermo-gravimetric balance under 15% CO2/85% Ar atmosphere. Adsorption selectivity of CO2 was studied by fixed-bed adsorption/desorption experiments. All the adsorbents displayed good thermal stability at 200 degrees C. Among them, MIP1b, with the higher amine content, exhibited the largest CO2 capacity, which maintained steady after 50 adsorption-desorption cycles. Although MIP3 showed the highest specific surface, the CO2 capacity was lower than that of MIP1b. CO2 adsorption mechanism of molecularly imprinted adsorbents was determined to be physical sorption according to the adsorption enthalpies integrated from the DSC heatflow profiles. The calculated separation factors of CO2 under 15% CO2/85% N-2 atmosphere were above 100 for all adsorbents.