Chapter 1.12 - Perturbed-Chain-SAFT: Development of a new equation of state for simple, associating, multipolar and polymeric compounds

Abstract

This chapter discusses the development of a new equation of state for simple, associating, multipolar, and polymeric compounds. A new physically based equation of state is proposed that is suitable for mole­cules of any molecular mass as well as for associating and polar substances and their mixtures. The model is termed Perturbed-Chain SAFT (PC-SAFT), and is derived by extending the perturbation theory of Barker and Henderson to chain molecules. The hard-chain fluid is consistently considered for the dispersion term. The molecular model is refined by individually accounting for molecular association and polar interactions. Three pure component parameters are required for nonpolar and nonassociating substances; two further parameters characterize association, and one additional parameter is needed for polar interactions. Copolymers can conveniently be modeled using the pure-component parameters of the appropri­ate homopolymers and one additional interaction parameter, only. It is found that using one constant parameter, convincing results are obtained for systems containing nonpolar as well as associating and polar substances, gases, solvent molecules, homopolymers, or copolymers.