New reference equation of state for associating liquids

An equation of state for associating liquids is presented as a sum of three Helmholtz energy terms: Lennard-Lones (LJ) segment (temperature-dependent hard sphere + dispersion), chain (increment due to chain formation), and association (increment due to association). This equation of state has been developed by extending Wertheim’s theory obtained from a resummed cluster expansion. Pure component molecules are characterized by segment diameter, segment-segment interaction energy, for example, Lennard-Jones u and E, and chain length expressed as the number of segments. There are also two association parameters, the association energy and volume, characteristic of each site-site pair. The agreement with molecular simulation data is shown to be excellent at all the stages of development for associating spheres, mixtures of associating spheres, and nonassociating chains. The model has been shown to reproduce experimental phase equilibrium data for a few selected real pure compounds.

[1]  K. E. Starling,et al.  Equation of State for Nonattracting Rigid Spheres , 1969 .

[2]  M. Wertheim.  Fluids of dimerizing hard spheres, and fluid mixtures of hard spheres and dispheres , 1986 .

[3]  R. Dickman,et al.  High density Monte Carlo simulations of chain molecules: Bulk equation of state and density profile near walls , 1988 .

[4]  K. Gubbins,et al.  Mixtures of polar and associating molecules , 1987 .

[5]  K. Gubbins,et al.  Theory and simulation of associating liquid mixtures , 1986 .

[6]  H. C. Andersen.  Cluster expansions for hydrogen‐bonded fluids. I. Molecular association in dilute gases , 1973 .

[7]  J. Prausnitz,et al.  LOCAL COMPOSITIONS IN THERMODYNAMIC EXCESS FUNCTIONS FOR LIQUID MIXTURES , 1968 .

[8]  P. Cummings,et al.  Analytic solution of the molecular Ornstein–Zernike equation for nonspherical molecules. Spheres with anisotropic surface adhesion , 1986 .

[9]  K. E. Starling,et al.  Improved analytical representation of argon thermodynamic behavior , 1980 .

[10]  K. Nakanishi,et al.  Molecular dynamics simulations on the hydration of fluoroalcohols , 1988 .

[11]  Yaoqi Zhou,et al.  Chemical association in simple models of molecular and ionic fluids , 1989 .

[12]  J. Prausnitz,et al.  Molecular thermodynamics for fluids at low and high densities. Part II: Phase equilibria for mixtures containing components with large differences in molecular size or potential energy , 1986 .

[13]  J. Barker,et al.  Perturbation Theory and Equation of State for Fluids. II. A Successful Theory of Liquids , 1967 .

[14]  G. M. Wilson,et al.  Vapor-Liquid Equilibrium. XI. A New Expression for the Excess Free Energy of Mixing , 1964 .

[15]  M. Wertheim,et al.  Fluids with highly directional attractive forces. II. Thermodynamic perturbation theory and integral equations , 1984 .

[16]  P. Cummings,et al.  Statistical mechanical models of chemical reactions: Analytic solution of models ofA+B⇌ABin the Percus-Yevick approximation , 1984 .

[17]  M. Wertheim,et al.  Fluids with highly directional attractive forces. I. Statistical thermodynamics , 1984 .

[18]  M. Wertheim,et al.  Thermodynamic perturbation theory of polymerization , 1987 .

[19]  E. A. Guggenheim.  Applications of Statistical Mechanics , 1966 .

[20]  B. G. Harper,et al.  Vapor-Liquid Equilibrium , 1957 .

[21]  George Jackson,et al.  SAFT: Equation-of-state solution model for associating fluids , 1989 .

[22]  M. Wertheim,et al.  Fluids with highly directional attractive forces. IV. Equilibrium polymerization , 1986 .

[23]  J. S. Rowlinson,et al.  Molecular Thermodynamics of Fluid-Phase Equilibria , 1969 .

[24]  John S. Rowlinson,et al.  Liquids and liquid mixtures , 1959 .

[25]  P. Cummings,et al.  Statistical mechanical models of chemical reactions , 1987 .

[26]  K. Gubbins,et al.  Phase equilibria of associating fluids : spherical molecules with multiple bonding sites , 1988 .

[27]  H. C. Andersen.  Cluster expansions for hydrogen bonded fluids. II. Dense liquids , 1974 .

[28]  M. Wertheim,et al.  Fluids with highly directional attractive forces. III. Multiple attraction sites , 1986 .

[29]  K. E. Starling,et al.  Equilibrium Thermodynamic Properties of the Mixture of Hard Spheres , 1971 .

[30]  J. Prausnitz,et al.  Statistical thermodynamics of liquid mixtures: A new expression for the excess Gibbs energy of partly or completely miscible systems , 1975 .

[31]  L. Verlet,et al.  Perturbation Theory and Equation of State for Fluids , 1969 .