PC-SAFT (perturbed chain SAFT) is an equation of state that is based on statistical associating fluid theory (SAFT). Like other SAFT equations of state, it makes use of chain and association terms developed by Chapman, et al from perturbation theory. [1] However, unlike earlier SAFT equations of state that used unbonded spherical particles as a reference fluid, it uses spherical particles in the context of hard chains as reference fluid for the dispersion term. [2]
PC-SAFT was developed by Joachim Gross and Gabriele Sadowski, and was first presented in their 2001 article. [2] Further research extended PC-SAFT for use with associating and polar molecules, and it has also been modified for use with polymers. [3] [4] [5] [6] A version of PC-SAFT has also been developed to describe mixtures with ionic compounds (called electrolyte PC-SAFT or ePC-SAFT). [7] [8]
The equation of state is organized into terms that account for different types of intermolecular interactions, including terms for
The equation is most often expressed in terms of the residual Helmholtz energy because all other thermodynamic properties can be easily found by taking the appropriate derivatives of the Helmholtz energy. [2]
Here is the molar residual Helmholtz energy.
where
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Gholam Ali Mansoori, G. Ali Mansoori also known as "GA Mansoori" is an Iranian-American scientist known for his research within energy, nanotechnology and thermodynamics. He is a professor at the Departments of Bioengineering, Chemical Engineering and also Physics at University of Illinois at Chicago.
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George Jackson,, , is a British professor of chemical physics in the Department of Chemical Engineering at Imperial College London. He is noted for developing molecular models that describe the thermodynamic properties of complex fluids; as one of the developers of statistical associating fluid theory (SAFT); and for his work in molecular systems engineering. His theoretical work has found a wide range of practical applications in industries such as gas extraction and emerging fields like carbon capture and storage.
Statistical associating fluid theory (SAFT) is a chemical theory, based on perturbation theory, that uses statistical thermodynamics to explain how complex fluids and fluid mixtures form associations through hydrogen bonds. Widely used in industry and academia, it has become a standard approach for describing complex mixtures. Since it was first proposed in 1990, SAFT has been used in a large number of molecular-based equation of state models for describing the Helmholtz energy contribution due to association.
