This paper suggests a mathematical model of processing experimental data that allows to plot the surface of the phase transition in near critical region, using the results of isochoric experiment. The model is based on proven approximation methods. The model was tested on 20 binary mixtures (10 mixtures of C2-C7 linear alkanes, five mixtures of propane and branched C5-C6 alkanes, two mixtures of haloalkanes, one mixture each of pentane with toluene, cyclohexane with benzene and toluene) with the difference in critical temperatures from 45 to 235 K. As the result, in the 0.5 less than (rhoDew)/(rhoC) less than 1.5 range of reduced density the average error in predicting temperatures of phase transition is 2.2 K, 1.2 K for critical temperatures, 3 K for maximum temperature of liquid and vapor phase coexistence.
Compounds
#
Formula
Name
1
C5H12
pentane
2
C7H8
toluene
3
C6H12
cyclohexane
4
C6H6
benzene
Datasets
The table above is generated from the ThermoML associated json file (link above).
POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied;
the numbers refer to the table of compounds on the left.