Biogas upgrading through blends of deep eutectic solvents and monoethanol amine: 4 E analysis (energy, exergy, environmental, and economic)

Blends of monoethanol amine (MEA) with an aqueous deep eutectic solvent (DES), with MEA present in various proportions of 5, 10, and 15 wt%, are used in process design for biogas upgrading.

Density, Viscosity and Free Energy of Activation for Viscous Flow of Monoethanol Amine (1) + H2O (2) + CO2 (3) Mixtures

Densities and viscosities of aqueous monoethanol amine (MEA) and CO2-loaded aqueous MEA are highly relevant in engineering calculations to perform process design and simulations. Density and viscosity of the aqueous MEA were measured in the temperature range of 293.15 K to 363.15 K with MEA mass fractions ranging from 0.3 to 1.0. Densities of the aqueous MEA were fitted for a density correlation. Eyring’s viscosity model based on absolute rate theory was adopted to determine the excess free energy of activation for viscous flow of aqueous MEA mixtures and was correlated by a Redlich–Kister polynomial. Densities and viscosities of CO2-loaded MEA solutions were measured in the temperature range of 293.15 K to 353.15 K with MEA mass fractions of 0.3, 0.4 and 0.5. The density correlation used to correlate aqueous MEA was modified to fit CO2-loaded density data. The free energy of activation for viscous flow for CO2-loaded aqueous MEA solutions was determined by Eyring’s viscosity model and a correlation was proposed to represent free energy of activation for viscous flow and viscosity. This can be used to evaluate quantitative and qualitative properties in the MEA + H2O + CO2 mixture.