Temperature Dependent Enthalpy of CO2 Absorption for Amines and Amino Acids from Theoretical Calculations at Infinite Dilution.

Abstract

The thermodynamics of carbamate formation from the reaction of amines or amino acids with CO2 in post combustion CO2 capture processes is studied in this work using computational chemistry calculations. Density functional theoretical calculations are coupled with the implicit and explicit solvation shell model presented by da Silva et al. [da Silva, E. F.; Svendsen, H. F.; Merz, K. M. J Phys Chem A 2009, 113, 6404] to calculate equilibrium constants for the reaction. These calculated temperature dependent equilibrium constants are used to derive temperature dependent heats of absorption for the carbamate formation reaction of amines and amino acids using the Gibbs Helmholtz equation. The computationally derived temperature dependent equilibrium constants and heats of absorption are compared against experimental results.