Figure 2.11: (a) Phase equilibrium of PE-n-pentane at T = 460 K. Comparison of the
predictions from the new equation of state (solid line, kʊ = 0.0065) and PC-SAFT (dashed
line, 1¾ — -0.005) with experimental data from Kiran et al. [91] (PE: Mw = 108 kg∕mol,
Mw/ Mn = 1.32). The dot-dashed line is the prediction from the new equation of state
with parameters extrapolated from the alkane series (kŋ = 0.0045). PE was assumed to
be monodisperse, (b) Phase equilibrium of PE-n-hexane at T = 500 K. Comparison of the
predictions from the new equation of state (solid line, kʊ = -0.004) and PC-SAFT (dashed
line, kʊ = -0.01) with experimental data from Schnell et al. [92] (PE: Mw = 382.8 kg∕mol,
Mw/ Mn = 1.19). PE was assumed to be monodisperse.
Figure 2.12b compares the results from the new EOS with experimental liquid-
liquid equilibrium (LLE) data for HDPE-n-hexane mixture. The experimental data
was collected by Kennis et. al. [95] who studied the influence of nitrogen on the phase
behavior of the system. The characterization of the molecular weight distribution of
polyethylene was based on the three molecular weights: Mra = 8 kg∕mol, Mw = 177
kg∕mol, and M2 = 1000 kg∕mol. This molecular distribution was modeled using six
pseudocomponents (see table 2.5) computed by Tork et. al. [94]. For comparison,
similar calculations were done using the PC-SAFT model with the same set of pseu-
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