Viscosity of 2-ethylhexan-1-amine (EHA)-diglyme, EHA-triglyme and EHA-tetraglyme non-aqueous solutions and its effect on initial absorption rate

The viscosities ( η ) of 2-ethylhexan-1-amine (EHA), diglyme , triglyme , tetraglyme and EHA-diglyme/triglyme/tetraglyme non-aqueous solutions were measured by using the NDJ-5S rotational viscometer at 101 kPa. The temperatures ( T ) ranged from 303.2 K to 323.2 K. The mass fractions of EHA ( w EHA ) ranged from 0.100 to 0.900. The viscosity was modeled and the calculated results agreed well with the experiments. The effects of w EHA and T on viscosity were demonstrated on the basis of experiments and calculations. The initial absorption rates of CO 2 ( r ) in EHA-diglyme/triglyme/tetraglyme non-aqueous solutions were measured, and the effects of viscosity, absorbent concentration and absorption rate constant of CO 2 ( k ) on initial absorption rates were demonstrated. Our research shows that in the temperature range of 303.2 K to 323.2 K, the proposed three non-aqueous absorbents have small solution viscosities (<3 mPa·s), which is beneficial to the mass transfer of CO 2 absorption and the initial absorption rate. Thus the proposed non-aqueous absorbents have good application potential in the field of CO 2 capture process.