Adsorptive separation of carbon dioxide by polyethyleneimine modified adsorbents

Utilization of carbon dioxide (CO2) has become an important global issue due to significant and continuous rise in atmospheric CO2 concentrations. To find a potential solution, two types of mesoporous materials, MCM-41 and MCM-48, were synthesized and impregnated with 30, 50 and 70 wt% of polyethyleneimine (PEI) in methanol to evaluate the performance of the materials in terms of CO2 adsorption. The materials were characterized by XRD, TGA, FTIR, TEM, SEM, N-2-physisorption and BET techniques. All the PEI-loaded materials exhibited substantially higher reversible CO2 adsorption-desorption behaviors with >99% recovery. The above study proved that MCM-48 is a better material as compared to MCM-41 for loading of PEI. The material with 50 wt% loading of PEI on MCM-48, showed maximum adsorption of 248 mg/g-PEI at 80 degrees C which is about 30 times higher than that of MCM-48 and about 2.3 times that of pure PEI.