Flexible, amine-modified silica aerogel with enhanced carbon dioxide capture performance

摘要

One kind of flexible, amine-modified silica aerogel (AMSA) was prepared using sol-gel method and ambient drying technology. The obtained AMSA displays excellent mechanical strength. It can endure up to ca. 80 % linear compression and spring back to more than 95 % of its original size reversible deformation during uniaxial compression tests. The formed AMSA has abundant micropore, mesopore and macropore. Its porosity is higher than 90 %. The amine groups are incorporated into the silica network via covalent bond. The porous structure and the content of amine groups can be easily changed by adjusting the synthesis condition. High mechanical property, abundant pores, high content and stable amine groups give the obtained AMSA excellent CO2 adsorption properties. Its CO2 adsorption capacity can reach 6.45 mmol/g in simulated ambient air under 1 bar of dry CO2, as well as good stability over 50 adsorption-desorption cycles.