Viscosity and density are thermophysical properties crucial to characterizing any kind of fluid
such as aqueous amines. These blends are becoming more and more relevant for their CO2
capture potential, such that having accurate viscosity and density measurements would prove
useful. Densities and viscosities of these mixtures at atmospheric pressure may be found in
the literature although it is more difficult to find values at high pressures, these potentially
proving interesting when seeking to provide a full description of these fluids.
Viscosity and density measurements at high pressures (up to 120 MPa) and at temperatures
between 293.15 and 353.15 K of MDEA + water and MEA + water mixtures (both from 10 %
to 40 % amine mass fraction) are presented in this work. Density measurements were
performed with an Anton Paar DMA HPM densimeter with an expanded uncertainty (k = 2)
less than ± 0.7 kg·m-3. A falling body technique was used to measure viscosities at high
pressures due to its sturdiness in terms of corrosion. Details of this latter equipment are
presented, including calibration using n-dodecane and uncertainty calculations, which give a
relative expanded uncertainty (k = 2) of less than ± 2.4 % for the highest viscosity and ± 2.9
% for the lowest.
