| abstract |
A carbon dioxide absorbent of an embodiment includes a heterocyclic amine expressed by Formula (1), and the heterocyclic amine having a pKa of any one amino group included 5 in a heterocyclic ring in Formula (1) in a range of 7.0 or more to 8.6 or less and an organic solvent having a boiling point of 150°C or more at 1 atm. A total mass of the heterocyclic amine and the organic solvent is 70 mass% or more to 100 mass% or less of the carbon dioxide absorbent. Each of R' to R4 in 10 Formula (1) is H, oxygen double-bonded with carbon of the heterocyclic ring, CH3, OH, or an alkyl chain optionally including a functional group. X1 in Formula (1) is H, CH3, CO, C(O)OC 2 H5 , C(O)OC 3 H7 , C(O)OCH(CH 3 ) 2 , C(O)OC(CH 3 ) 3 , C(O)OCH 3 , C(O)CH3 , or C(O)C2H5. 6- 11 2- 14 Fig. 2 |