High efficiency nanocomposite sorbents for CO2 capture based on amine-functionalized mesoporous capsules

Abstract

A novel high efficiency nanocomposite sorbent for CO₂ capture has been developed based on oligomeric amine (polyethylenimine, PEI, and tetraethylenepentamine, TEPA) functionalized mesoporous silica capsules. The newly synthesized sorbents exhibit extraordinary capture capacity up to 7.9 mmol g⁻¹ under simulated flue gas conditions (pre-humidified 10% CO₂). The CO₂ capture kinetics were found to be fast and reached 90% of the total capacities within the first few minutes. The effects of the mesoporous capsule features such as particle size and shell thickness on CO₂ capture capacity were investigated. Larger particle size, higher interior void volume and thinner mesoporous shell thickness all improved the CO₂ capacity of the sorbents. PEI impregnated sorbents showed good reversibility and stability during cyclic adsorption–regeneration tests (50 cycles).