Designing Adsorbents for CO₂ Capture from Flue Gas-Hyperbranched Aminosilicas Capable of Capturing CO₂ Reversibly

Abstract

Carbon dioxide adsorption from a simulated flue gas stream was successfully performed with a hyperbranched aminosilica (HAS) material. The HAS was synthesized by a one-step reaction, spontaneous aziridine ring-opening polymerization off of surface silanols, to form a 32 wt % organic/inorganic hybrid material. The adsorption measurements were performed in a fixed-bed flow reactor using humidified CO 2 . The advantage of this adsorbent over previously reported adsorbents is the stability of the organic groups covalently bound to the silica support compared to those made by physisorbed methods. Furthermore, a large CO 2 capacity (∼3 mmol CO 2 /g adsorbent) associated with the high loading of amines was observed.