(a)
О 0.2 0.4 0.6 0.8 1
x(n-C24)
Figure 2.9: (a) Vapor-Iiquid equilibrium of n-tetracosane-hexane mixture at T = 623
K. (b) Vapor-Iiquid equilibrium of n-hexatriacontane-hexane mixture at T = 621.8 K.
Comparison of the predictions from the new equation of state (solid lines) and PC-SAFT
(dashed lines) with experimental data (symbols) from Joyce et. al. [90].
2.3.3 Polymer systems
The parameters from the n-alkane series on extrapolation to molecular weights
corresponding to polymers, asymptotically tend to limiting values. Based on this
extrapolation, the parameters obtained for high density polyethylene (HDPE) were
m∕Mw — 0.02268, σ — 4.4358A and e/к = 278.79 K. An average absolute deviation
of 8% was obtained for the density data of HDPE in the pressure range from 1 to
2000 bar, and the temperature range from 410 to 473 K. With these parameters
and kʊ = 0.0045, the phase behavior of HDPE-n-pentane mixture was calculated
as shown by dot-dashed curve in figure 2.1 la. These calculations show that the
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