The availability of molecular structural and spectrographic data has enabled the calculation of the ideal gas thermodynamic functions [formula omitted] for thirty eight halogenated benzenes. The thermodynamic functions are given for temperatures between 273.15° K. and 1500° K., at one atmosphere. The contribution of the anharmonicity effect to the thermodynamic properties is discussed. Additionally, a method is described for making real gas corrections to the ideal gas thermodynamic functions, however, only over a limited range of pressure and temperature (15 atm. to 0.25 atm. 273.15° K. to 1000° K.). This method, based on the Berthelot equation of state, requires the critical temperature and pressure, which are summarised in this work for several of the halogenated benzenes. As an example of the method, the real gas thermodynamic functions for fluorobenzene are shown, at pressures between 10 atm. and 0.25 atm. Finally the thermal stability of the halogenated benzenes is discussed and the temperatures over which the ideal gas thermodynamic functions are applicable are indicated. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate

A systematic study of the excess thermodynamic properties of two-ring compounds and n-alkanes was conducted. The excess enthalpies were determined at 288,15 K and 298,15 K by using a flow microcalorimetric technique. The excess volumes of tetralin and cycloalkanes, and tetralin and --alkans at 288,15 K and 298,15 K were determined by using a vibrating tube densitometer. The results showed trends relating to the size and shape of the n-alkane and cycloalkan molecules. The theory developed by Flory was applied to the decalin + cycloalkane and + n-alkane systems and this gave qualitative predictions of the excess enthalpies from the excess volumes and vice versa. / KMBT_363 / Adobe Acrobat 9.53 Paper Capture Plug-in

The objective of this research was to apply the TK!Solver program for thermodynamic calculations. The TK!Solver program is equation-solving software that can solve both linear and non-linear sets of equations. To achieve the above objective, six programs have been developed. Program ESTATE.TK calculates volumetric properties of compounds using the ideal gas law, Pitzer correlation, van der Waals, Redlich-Kwong, Dieterici, or Berthelot equation of state. The volumetric properties include temperature, pressure, volume, and compressibility factor. Program RESIDUAL.TK calculates residual and total properties of compounds as a function of temperature and pressure using the Pitzer correlation, van der Waals, or Redlich-Kwong equation of state. The residual and total properties include residual volume, residual internal energy, residual enthalpy, and residual entropy. Program FRENERGY.TK calculates standard free energy of formation, standard enthalpy of formation, and standard entropy of formation for a compound or a reaction as a function of temperature. This program also calculates the equilibrium constant for a reaction as a function of temperature. Program CHON.TK calculates the equilibrium composition for an adiabatic or non-adiabatic reactor as a function of the temperature and pressure of the reactor, hydrogen-to-oxygen ratio, and nitrogen-to-oxygen ratio in the feed. The feed to the reactor consists of the elements carbon, hydrogen, oxygen, and nitrogen. The products of the reactor are methane, water, carbon monoxide, carbon dioxide, hydrogen, and nitrogen. Program CRITICAL.TK furnishes critical data for more than fifty compounds. The critical data includes critical temperature, critical pressure, critical volume, critical compressibility factor, and the acentric factor. Programs ESTATE.TR and RESIDUAL.TK have access to data file CRITICAL.TK for state property calculations. Program DATBANK1.TK supplies heat capacity data, heat of formation, and entropy of formation data for more than one hundred compounds. Programs RESIDUAL.TK and FRENERGY.TK have access to data file DATBANK1.TK for enthalpy and entropy calculations. These six programs may be considered as a basis for an "expert" system for thermodynamic calculations. Data can be easily added to extend the calculations to include additional compounds. / M.S.

Aqueous-polymer two-phase systems consist of various combinations of water, polymer(s), low molecular weight component(s), and salts. These aqueous-polymer systems are comprised of two phases, each of which contains about 90 percent (by weight) water. Due to some very unique properties, these systems have been applied to separations involving biological molecules for at least a quarter of a century. In particular, these systems are inexpensive, efficient, and provide a mild (aqueous) and possibly stabilizing environment for fragile biologically-active molecules. These systems may also be designed for a high degree of selectivity. Although much effort has been expended in the area of polymer solution theory, the theory of why these systems exhibit this extraordinary two-phase behavior that characterizes them as viable liquid-liquid extraction systems for use with biologically-active molecules is not completely understood. A thermodynamic model which could accurately represent the phase equilibria exhibited by these systems would be useful for the design of systems for use in many different applications. A potpourri of thermodynamic models and their underlying theoretical structure have been critically studied for their particular application to predicting the phase behavior of aqueouspolymer two-phase systems. In particular, the Flory-Huggins model is reviewed (with discussion of its inadequacies and subsequent modifications); the theory of Ogston; the model by Heil; several local composition models (NRTL, Wilson, and UNIQUAC); and two group-contribution models (ASOG and UNIFAC) are all discussed. The development of a solvent-electrolyte model (Chen's model) based on local composition theory (in particular the NRTL model) is reviewed, and the subsequent possible modification of this theory for solvent-polymer-electrolyte systems is discussed. The pros and cons of each model are discussed and qualitative results are given. Quantitative comparisons with experimental data are made with several of these models when appropriate data are available. The main conclusions of this work are: 1. A major limitation to the modeling of these aqueous-polymer two-phase systems is the lack of experimental data. Sufficient, accurate data is needed for the reduction of meaningful thermodynamic parameters by which thermodynamic models can be tested for their applicability. There exists a definite need for the generation of accurate, meaningful thermodynamic data from well characterized systems. 2. The most promising model identified in this work is the theory of Ogston. First, the model is based on the virial expansion and is thus quite suitable for dilute solutions. The Ogston model is the simplest theoretically-relevant dilute-solution model. Second, it appears to be easily extended to solvent-polymer-electrolyte solutions. 3. The Flory equation of state approach appears to be promising for representing polymer solutions. The free volume dissimilarity effect on which it is based is extremely important for solvent-polymer solutions. The most important aspect of this theory is its ability to predict lower critical solution temperature (LCST) behavior -- for which the Flory-Huggins theory is totally inadequate. / M.S.