CO2 Solubility in diethylenetriamine (DETA) and triethylenetetramine (TETA) aqueous mixtures: Experimental investigation and correlation using the CPA equation of state

Abstract

CO2 capture is of profound significance to mitigate emissions from fossil fuel combustion. Absorption technologies represent a mature approach for post-combustion CO2 capture, and, in this direction, the development of new solvent systems, alternative to aqueous ethanolamine (MEA) solutions that are currently used, has attracted significant research interest. Among the solvents that have been suggested, polyamines, such as diethylenetriamine (DETA) and triethylenetetramine (TETA), represent interesting candidates for use in amine mixture solvents. This work presents new high pressure experimental data for the solubility of CO2 in aqueous DETA and TETA solutions. The former system is investigated using two experimental techniques in order to expand the investigated pressure range. In addition, the obtained new experimental data are used to parameterize the Cubic-Plus-Association Equation of State (CPA EoS), which, in turn, coupled with the pseudo-chemical reaction approach, is used to satisfactorily describe the VLE behavior of the studied systems.

Keywords

• CO2 capture
• polyamines
• CPA
• chemical absorption
• DETA
• TETA