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

Abstract

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.