Polyethylenimine (PEI)-impregnated resin adsorbent with high efficiency and capacity for CO2 capture from flue gas

A highly efficient solid-amine adsorbent with excellent CO2 capacity from flue gas was successfully prepared using polyethyleneimine (PEI)-impregnated resin HPD450 in this study. The adsorbents were characterized by scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FTIR), N2 adsorption–desorption, thermogravimetric analysis (TGA) techniques and elemental analysis (EA). The CO2 adsorption behaviors of the adsorbent were studied for their adsorption capacity, kinetics, thermodynamics and stability. The optimal adsorbent (HPD450/PEI-50) exhibited an excellent adsorption capacity of 4.44 mmol g−1 for pure CO2 and 3.62 mmol g−1 for 15 vol% CO2. Moreover, HPD450/PEI-50 retained an average capacity of 3.58 mmol g−1 under flue gas for 90 consecutive adsorption cycles. The adsorption/desorption process of CO2 on HPD450/PEI-50 was investigated using in situ FTIR. The capture of carbon dioxide in the simulated flue gas stream also demonstrated that moisture had a promoting effect on CO2 adsorption. This design of the high-performance HPD450/PEI-50 with a fantastic CO2 capacity could provide an up-and-coming candidate for CO2 capture from flue gas.