2022 Annual Meeting
(143h) Amine Functionalization of Hyper-Cross-Linked Polymer (HCPs) for CO2 Separation from Biogas
Authors
Hyper-cross-linked polymeric (HCP) resins are organic porous materials used in CO2 adsorption, primarily because of their properties such as low density, high specific surface area, and high mechanical stability [2]. HCPs have tunable porous structures and rigid networks that prevent the porous wall from collapsing owing to their high degree of crosslinking, making them excellent solid adsorbents. Recently, amine-modified HCP resins have been proposed and evaluated for CO2 separation from flue gases and air [3]. However, its use in biogas upgrading and the economic feasibility evaluation of such adsorbents' practical application has not been explored in detail [4]. This work studied the use of PEI-impregnated resin sorbent for CO2 separation from biogas. The sorbent exhibited the highest adsorption capacity of 2.7 mmolCO2/gads at 30% PEI loading, increasing to 2.9 mmolCO2/gads in the presence of moisture, and remained stable for several adsorption-desorption cycles. In-situ DRIFTS studies showed that CO2 adsorption on PEI-impregnated sorbent is consistent with the zwitterion reaction mechanism, and the sorbent could be regenerated completely at 100°C. The upgrading cost of biogas is primarily dominated by the operating cost of regeneration and the adsorbent cost. Economic feasibility analysis projected that PEI-impregnated resin sorbent requires less capital and operating cost than conventional biogas upgrading technologies. Therefore, PEI-functionalized HCPs resins are promising for CO2 separation from biogas.