(460c) Efficient CO2 Sorbents Based On Cost-Effective Silica Foams with Ultra-Large Mesopores

Increases in atmospheric carbon dioxide have been implicated as one of the main causes of global climate change. Post-combustion capture shows the greatest near-term potential for reducing CO₂ emissions. The current benchmark process for post-combustion capture is absorption using amine solutions, which suffers from relatively low energy efficiency and issues associated with the use of liquid amine solvents such as equipment corrosion, solvent loss, and toxicity. Adsorption using supported amine sorbents provides a promising alternative to conventional amine scrubbing. However, CO₂ capture in practical applications has been impeded primarily by limited sorbent capacity and recyclability, and relatively high sorbent cost. Here we present a series of high-capacity amine sorbents supported on a cost-effective silica foam with ultra-large mesopores. The sorbents exhibit fast CO₂ capture kinetics, high adsorption capacity, as well as good stability over multiple adsorption-desorption cycles. A theoretical analysis is provided for the first time relating the support structure to sorbent performance, which may direct the structural optimization of sorbent supports.