Physicochemical properties important for carbon dioxide absorption in aqueous methyldiethanolamine

The objective of thls work Is to experimentally determlne the diffusion coefflclent and freegas solubllity of carbon dloxlde In aqueous methyldlethanolamlne (MDEA). Solutlon vlscoslty and density were also measured. Experiments covered the concentratlon range 0-50 wt % MDEA for temperatures between 15 and 50 OC. Slrce the solubllity and dlffuslvlty of a gas cannot be meawed directly In a system In which A reacts, the N20 analogy method was used In thls work to estimate these propertles for the system C0,-aqueous MDEA solutlons. SolubllAles were measured volumetrlcally In an equlllbrlum cell, and dlffuslon coefflclents were measured In a lamlnar liquid jet absorber for low MDEA concentratlons and a wetted-sphere absorber for hlgh MDEA concentrations. Properties were correlated by convenlent equations which were found to be In excellent agreement with the experlmental data.