Abstract2‐(2‐Aminoexthoxy)ethanol or diglycolamine (DGA) is a CO2 absorption solvent that is suitable to treat natural gas, flue gas, and biogas or landfill gas. Equilibrium CO2 solubility in concentrated aqueous DGA solvents with varying molality was measured under absorption and desorption conditions at different temperatures. Viscosity and surface tension of the solvent before absorption, after absorption, and after desorption were determined. With increasing DGA molality, CO2 loading remained constant until the number of moles of DGA exceeded the number of moles of water. For a given DGA molality, with higher CO2 loading, viscosity increased exponentially and surface tension rose with a power of two.