Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

ABSTRACT

The present work represents a continuation of a former study where the simultaneous determination of thermal and mutual diffusivity for binary mixtures of n-octacosane (n-C28H58) with dissolved carbon monoxide (CO), hydrogen (H2), or water (H2O) by using dynamic light scattering (DLS) was demonstrated. Here, the same properties are studied for binary mixtures of the n-alkanes n-dodecane (n-C12H26) or n-tetracontane (n-C40H82) with dissolved CO, H2, or H2O. In most cases, expanded relative uncertainties (k = 2) ranging from 2 to 12 % and 3 to 25 % for the thermal and mutual diffusivities could be obtained. The experimental mutual diffusivities for mixtures of n-C12H26 with CO, H2, or H2O measured at temperatures from 398 to 524 K and pressures from 0.2 to 4.2 MPa at saturation conditions agree well with molecular dynamics (MD) simulations using atomistic models and with experimental data from literature. Binary mixtures of n-C40H82 with dissolved CO, H2, or H2O were investigated in a temperature range from 447 to 498 K and pressures from 0.3 to 3.9 MPa. For mixtures with n-C40H82, the accessible temperature range was limited due to a change in the optical characteristics of the sample at elevated temperatures where DLS measurements suffered from absorption effects and particle scattering.