In a preceding project, functional forms for “short” Helmholtz energy equations of state for typical nonpolar and weakly polar fluids and for typical polar fluids were developed using simultaneous optimization. In this work, the coefficients of these short forms for the equations of state have been fitted for the fluids acetone, carbon monoxide, carbonyl sulfide, decane, hydrogen sulfide, 2-methylbutane (isopentane), 2,2-dimethylpropane (neopentane), 2-methylpentane (isohexane), krypton, nitrous oxide, nonane, sulfur dioxide, toluene, xenon, hexafluoroethane (R-116), 1,1-dichloro-1-fluoroethane (R-141b), 1-chloro-1,1-difluoroethane (R-142b), octafluoropropane (R-218), 1,1,1,3,3-pentafluoropropane (R-245fa), and fluoromethane (R-41). The 12 coefficients of the equations of state were fitted to substance specific data sets. The results show that simultaneously optimized functional forms can be applied to other fluids out of the same class of fluids for which they were optimized without significant loss of a...

Short Fundamental Equations of State for 20 Industrial Fluids

A compendium of phase change enthalpies published in 2010 is updated to include the period 1880–2015. Phase change enthalpies including fusion, vaporization, and sublimation enthalpies are included for organic, organometallic, and a few inorganic compounds. Part 1 of this compendium includes organic compounds from C1 to C10. Part 2 of this compendium, to be published separately, will include organic and organometallic compounds from C11 to C192. Sufficient data are presently available to permit thermodynamic cycles to be constructed as an independent means of evaluating the reliability of the data. Temperature adjustments of phase change enthalpies from the temperature of measurement to the standard reference temperature, T = 298.15 K, and a protocol for doing so are briefly discussed.

Phase Transition Enthalpy Measurements of Organic and Organometallic Compounds. Sublimation, Vaporization and Fusion Enthalpies From 1880 to 2015. Part 1. C1-C10

A formulation for the thermodynamic properties of ethanol (C2H5OH) in the liquid, vapor, and saturation states is presented. The formulation is valid for single-phase and saturation states from 250 to 650 K at pressures up to 280 MPa. The formulation includes a fundamental equation and ancillary functions for the estimation of saturation properties. The experimental data used to determine the fundamental equation include pressure-density-temperature, ideal gas heat capacity, speed of sound, and vapor pressure. Saturation values computed from the ancillary functions were used to ensure thermodynamic consistency at the vapor-liquid phase boundary. Comparisons between experimental data and values computed using the fundamental equation are given to verify the uncertainties in the calculated properties. The formulation presented may be used to compute densities to within ±0.2%, heat capacities to within ±3%, and speed of sound to within ±1%. Saturation values of the vapor pressure and saturation densities are represented to within ±0.5%, except near the critical point.

A Fundamental Equation for Calculation of the Thermodynamic Properties of Ethanol

Experimental reexamination of selected partition coefficients from Rohrschneider's data set

The renormalized perturbation theory for polarizable polar fluids of Wertheim is applied in combination with a dipole contribution for non-spherical molecules to account for the non-additive induction interactions due to the polarization of molecules. A comparison to simulation data of pure polarizable dipolar fluids and mixtures reveals a good to excellent agreement between the renormalized perturbation theory and the simulations. The model framework is applied with the Perturbed-Chain SAFT equation of state to model phase equilibria of mixtures containing strongly polar components. The considered values of dipole moments and of average molecular polarizabilities stem from independent sources, and there is thus no additional adjustable parameter introduced along with the polar contributions to the equation of state. It is confirmed that accounting for dipolar interactions not only reduces the value of the binary interaction parameter, but in many cases significantly improves the description of pure-component and mixture phase equilibria. Accounting for molecular polarizability and the dipole induction effects only leads to slightly improved results compared to the case where a permanent dipole moment is considered in the calculations. © 2006 American Institute of Chemical Engineers AIChE J, 2006

An equation of state contribution for polar components: Polarizable dipoles

Vapor-liquid equilibrium for the binary systems propionitrile-ethylbenzene and acetonitrile-ethyl acetate, -ethyl alcohol, and -toluene

Total-pressure vapor-liquid equilibrium data for binary systems of chlorobenzene with nitromethane, ethanol, benzene, and 1-chlorobutane

Total-pressure vapor-liquid equilibrium data for binary systems of 1-chlorobutane with ethyl acetate, acetonitrile, nitromethane, and acetone

Total-pressure vapor-liquid equilibrium data for binary systems of dichloromethane with pentane, acetone, ethyl acetate, methanol, and acetonitrile

The methods used to evaluate excess volume data are described. The evaluation results for the benzene+cyclohexane system are presented. The needs for new experimental data are defined.

Ol Muthu

Papers

Vapor-liquid equilibrium for the binary systems propionitrile-ethylbenzene and acetonitrile-ethyl acetate, -ethyl alcohol, and -toluene

Total-pressure vapor-liquid equilibrium data for binary systems of chlorobenzene with nitromethane, ethanol, benzene, and 1-chlorobutane

Total-pressure vapor-liquid equilibrium data for binary systems of 1-chlorobutane with ethyl acetate, acetonitrile, nitromethane, and acetone

Total-pressure vapor-liquid equilibrium data for binary systems of dichloromethane with pentane, acetone, ethyl acetate, methanol, and acetonitrile

Evaluation of Binary Excess Volume Data for C6 Hydrocarbons. Benzene+Cyclohexane