Density and viscosity correlations and thermodynamic properties in post-combustion CO2 capture processes

Abstract

Physicochemical properties such as density and viscosity are critical in the design of process equipment in the post combustion amine-based CO2 capture process because they appear in the majority of the mass transfer and interfacial area correlations of the random and structured packing in the absorption column.

Potential absorbents' density and viscosity have been tested and published in the literature at various amine concentrations and temperatures. The Gibbs free energy as molar properties is derived using observed viscosity and density from the literature and fitted to the empirical correlations to reflect the data and equations that may be used to determine other physical characteristics. Estimated coefficients from the correlation fitted data, used to develop a new correlation for the free energy of activation and excess free energy of activation.

The maximum deviation AARD of the Redlich and Kister correlation which used for data fitting was less than 4% which is acceptable, and the AARD of the new correlation developed in this work was under 1% which shows a quite good accuracy.

The influence of pressure on the trend changes of the free energy of activation and excess free energy of activation might be fascinating in this task because it was done using measured data under atmospheric conditions.