Amine-grafted mesoporous copper silicates as recyclable solid amine sorbents for post-combustion CO2 capture

Amine-functionalized nanomaterials have significant potential in CO 2 capture technology because of their low energy consumption, stable performance, and high regeneration capacity. Novel amine-functionalized adsorbents composed of copper silicate nanospheres (CSNSs) grafted with mono-, di- and tri-aminosilanes were synthesized for CO 2 capture. The synthetic process and formation mechanism were systematically investigated using transmission electron microscopy, X-ray photoelectron spectroscopy, fourier transform infrared spectroscopy, and N 2 physisorption analysis, etc. The copper silicates with rich surface hydroxyl groups, significant surface areas and mesoporous structures facilitated chemical modification of amines, leading to a high CO 2 adsorption capacity (a maximum CO 2 uptake of 47.88   mg/g) and excellent cyclic regenerability (maximum deviation of 3.51% after 20-times test) for CSNS-TA. In addition, the CO 2 capture process was carried out under relatively mild conditions, e.g., adsorption at 298   K, desorption at 373   K and ambient pressure , suggesting that these amine-modified CSNSs have potential as solid sorbents for CO 2 capture.