Experiment and model for the viscosity of carbonated piperazine-N-methyldiethanolamine aqueous solutions

The viscosities of both CO2-unloaded and CO2-loaded piperazine (PZ) promoted N-methyldiethanolamine (MDEA) aqueous solutions were measured by using a NDJ-1 rotational viscometer, with temperatures ranging from 293.15 to 323.15 K. The total mass fraction of amines was fixed as 0.5 and the mass fraction of PZ ranged from 0.025 to 0.15. The CO2 loading ranged from 0 to 0.6. The Weiland equation was used to correlate the viscosities and the calculated results agreed well with the experiments. The effects of temperature, mass fraction of amines and CO2 loading on the viscosity were demonstrated.