Abstract This work focused on the synthesis of new tertiary amines by varying the alkyl chain length with/without hydroxyl group in the structure. The effect of chemical structure of newly synthesized tertiary amines; 4-(dimethylamino)-2-butanol (DMAB), 4-(dipropylamino)-2-butanol (DPAB), 4-(dibutylamino)-2-butanol (DBAB), 4-((2-hydroxyethyl)(methyl)amino)-2-butanol (HEMAB) and 4-((2-hydroxyethyl)(ethyl)amino)-2-butanol (HEEAB) were evaluated based on CO 2 equilibrium solubility and cyclic capacity, as well as rates and heats of CO 2 absorption and regeneration. The results showed that three amines (i.e. DMAB, HEMAB and HEEAB) had the highest CO 2 absorption capacity (0.88, 0.44 and 0.68 mol CO 2 /mol amine at 313 K temperature and 15 kPa CO 2 partial pressure), and cyclic capacity (0.52, 0.26 and 0.40 at 313–353 K temperature range, 15 kPa CO 2 partial pressure). These amines also had fast CO 2 absorption rate (0.082, 0.111 and 0.142 mol CO 2 /min) and CO 2 regeneration rate (0.512, 0.452 and 0.295 mol CO 2 /min) while maintaining low heat of CO 2 absorption (−34.17, −56.21 and −69.79 kJ/mol CO 2 ) and heat input of CO 2 regeneration (39.73, 60.48 and 72.44 kJ/mol CO 2 ). Based on these results, DMAB, HEMAB, and HEEAB can be considered to be promising amine components for blending for a post combustion CO 2 capture process.