Investigation of viscosity, activation energy and CO2 diffusion coefficient for N-methyl-1,3-propane-diamine, N-(2-aminoethyl)ethanolamine and 1,4-butanediamine activated 2- diethylaminoethanol aqueous solutions

• Viscosities of AEEA, MAPA and BDA activated DEAE aqueous solutions were measured; • Experiments were modeled satisfactorily by using Weiland equation; • Activation energy and CO 2 diffusivity were determined from viscosity experiments; • Effects of temperature and mass fraction on viscosity, E a and D CO2 were illustrated. The viscosities of N -(2-aminoethyl)ethanolamine (AEEA), 1,4-butanediamine (BDA) and N-methyl- 1,3-propane- diamine (MAPA) activated 2- diethylaminoethanol (DEAE) aqueous solutions were measured at temperatures ( T ) from 303.2 K to 323.2 K, respectively. The DEAE mass fractions ( w DEAE ) and the other three amines ( w AEEA / w BDA / w MAPA ) are 0.300 to 0.500 and 0.050 to 0.150 respectively. The Weiland equation was used to calculate the viscosity of these three solutions, and the calculation results were satisfied with data of the experimental results. With the aid of experimentally determined viscosity data, the activation energy ( E a) of these three solutions was predicted through the Arrhenius formula. With the help of the viscosity data and the diffusion coefficient model of CO 2 in water, the CO 2 diffusion coefficient ( D CO2 ) in these three solutions was calculated. The quantitative relationship between the calculated values (viscosity, activation energy and diffusion coefficient) and the operation conditions (solution mass fraction and temperature) was analyzed. Our results show that the DEAE-BDA absorbent has better application potential due to its lower viscosity, higher CO 2 diffusion coefficient and lower activation energy.