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

Abstract

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.