Measurement and modeling of density and viscosity of nonaqueous systems (secondary alkanolamines+2-hexyloxyethanol+CO2) at temperatures of (293.15-353.15) K

Knowledge of physicochemical properties of new developed absorbents is important for understanding the hydrodynamics and mass transfer behaviors during CO2 absorption. In this work, density and viscosity of partially carbonated nonaqueous systems containing amine and 2-(hexyloxy)ethanol (EGHE) were measured at temperatures of (293.15-353.15) K and 101.3 kPa. Three secondary alkanolamines (i.e., 2-(methylamino)ethanol, 2(ethylamino)ethanol and 2-(butylamino)ethanol) were investigated in the concentration range of 10-60 mass%. It was found that viscosities of the carbonated solutions presented an exponential change with the temperature, CO2 loading and amine concentration. However, an approximately linear increase in density with the decreasing temperature and the increasing CO2 loading was observed for all the studied blends. Property data of the CO2- loaded solutions can be represented by two proposed models with simple parameters based on CO2-free property data. These models can provide good prediction of thermophysical properties in a CO2 capture process.