Solubility, absorption heat and mass transfer studies of CO2 absorption into aqueous solution of 1-dimethylamino-2-propanol

• CO2 solubility in 1DMA2P was measured at various T   and PCO2PCO2.
• The CO2 absorption heat of 1DMA2P was got and was lower than MEA and MDEA.
• The ion speciation plots were generated using the pH calculation method.
• The overall mass transfer coefficient of 1DMA2P was investigated and compared.

In this work, the CO2 absorption performance of aqueous 1-dimethylamino-2-propanol (1DMA2P) was comprehensively investigated in terms of CO2 equilibrium solubility, CO2 absorption rate, CO2 absorption heat, and mass transfer efficiency. The CO2 equilibrium solubility in 2 M 1DMA2P was measured over the temperature range of 298–333 K and CO2 partial pressure range of 8–101 kPa. The results showed that the CO2 equilibrium solubility of 1DAM2P was higher than those of conventional amines, MEA and MDEA. The CO2 absorption heat of 1DMA2P based on the Gibbs–Helmholtz equation was found to be −30.5 kJ/mol, which suggests that 1DMA2P needs a lower regeneration energy as compared with MEA and MDEA. Ion speciation (including 1DMA2P, 1DMA2PH+, HCO3−, CO32−) plots obtained from the pH method were also generated at the temperatures of 298 K and 313 K. In addition, the overall mass transfer coefficient (KGav) of 1DMA2P in a packed column was also experimentally obtained and compared with those of MEA and MDEA. The ranking was: MEA > 1DMA2P > MDEA.