then applying perturbation to hard-chain reference fluid to obtain an EOS for SW
chain fluids. These two different approaches to develop an EOS for attractive chains
is depicted in fig. 2.1.
Figure 2.1: Schematic of the associating molecules as modeled in TPTl.
The EOS for SW chain fluids developed by Gross and Sadowski has been extended
to real fluids [48, 79]. This EOS, labelled as perturbed-chain SAFT (or PC-SAFT),
accurately describes the phase behavior and thermophysical properties of pure long
chain molecules and their mixtures. Comparisons with HR-SAFT showed that PC-
SAFT is clearly superior. Hence, PC-SAFT is now recognized as being more accurate
and versatile engineering EOS. However, as with the HR-SAFT, PC-SAFT is not able
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