Table 5 Investigated PR EoS based thermodynamic models.

PR EoS:	\(P=\frac{RT}{\overline{V }-b(x)}-\frac{a(T,x)}{\overline{V }\left[\overline{V }+b(x)\right]+b\left[\overline{V }-b(x)\right]}\)
PR + vdW^a	\(a=\sum_{i}\sum_{j}{{x}_{i}x}_{j}\sqrt{{a}_{i}{a}_{j}}(1-{k}_{ij})\) \(b=\sum_{i}{x}_{i}{b}_{i}\)
PR + WS + Wilson^b	\(\frac{a}{b}=\sum_{i}{x}_{i}\left(\frac{{a}_{i}}{{b}_{i}}\right)+\frac{{\overline{G} }^{E}}{{C}_{\mathrm{WS}}}\) \(b=\frac{\sum_{i}\sum_{j}{{x}_{i}x}_{j}\left(\frac{{b}_{i}+{b}_{j}}{2}-\frac{\sqrt{{a}_{i}{a}_{j}}}{RT}\right)}{1-\sum_{i}{x}_{i}\left(\frac{{a}_{i}}{{b}_{i}RT}\right)-\frac{{\overline{G} }^{E}}{{C}_{\mathrm{WS}}RT}}\)
PR + HV + COSMOSAC^c	\(\frac{a}{b}=\sum_{i}{x}_{i}\left(\frac{{a}_{i}}{{b}_{i}}\right)+\frac{{\overline{G} }^{E}}{{C}_{\mathrm{HV}}}\) \(b=\sum_{i}{x}_{i}{b}_{i}\)

*a_i and b_i are determined from critical temperature, critical pressure, and acentric factor of component i as described in the literature⁵⁰.
^ak_ij is an adjustable binary interaction parameter.
^b \({C}_{\mathrm{WS}}=\mathrm{ln}\left(\sqrt{2}-1\right)/\sqrt{2}\)^60,61. Excess Gibbs energy is determined from the Wilson model⁶²: \({\overline{G} }^{E}=-RT\sum_{i}{x}_{i}\mathrm{ln}\left(\sum_{j}{x}_{j}{\Lambda }_{ij}\right)\) with \({\Lambda }_{ij}=\mathrm{exp}(-{u}_{ij}/RT)\) with \({u}_{ij}\) being adjustable binary interaction parameters.
^c \({C}_{\mathrm{HV}}=\mathrm{ln}\left(2\right)\)⁶³. Excess Gibbs energy \({\overline{G} }^{E}\) is calculated from the COSMOSAC model^58,59 without any system-specific adjustable parameter.

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