Carbohydrate based hyper-crosslinked organic polymers with –OH functional groups for CO2 separation

Abstract

Recently, microporous organic polymers, especially those hyper-crosslinked from functionalized aromatic monomers, have been shown to be effective for CO₂ capture and storage with considerable capacity and selectivity. Herein, a class of novel microporous hyper-crosslinked polymers (HCPs), based on green and renewable carbohydrates, was synthesized by Friedel–Crafts alkylation for carbon capture and storage by hydrogen bonding and dipole–quadrupole interactions. These carbohydrate polymers, which have BET surface areas around 800 m² g⁻¹, can absorb a considerable amount of CO₂ with the CO₂/N₂ selectivity up to 42 at 273 K, and 96 under 100 kPa in the mixed gases (0.15 mol CO₂ and 0.85 mol N₂). Furthermore, we experimentally and computationally studied the structures of carbohydrate backbones and determined several features that govern their CO₂ absorption ability, which sheds light on understanding the structure/function relationship for designing better CO₂ separation materials.