| abstract |
A carbon dioxide adsorbent including silica gel and an amine compound carried by the silica gel. The silica gel has a spherical shape, a particle size ranging from 1 mm to 5 mm inclusive, an average pore diameter ranging from 10 nm to 100 nm inclusive, a pore volume ranging from 0.1 cm 3 /g to 1.3 cm 3 /g inclusive, and a waterproof property N that is defined by an expression (1) and that is not lower than 45%,n n N =( W/W 0 )×100 (1)n where N is the waterproof property in percentage (%) of the silica gel, W 0 is a total number of particles of the silica gel immersed in water, W is a number of particles of the silica gel not subjected to breakage out of W 0 . |