Hexafluoride thermodynamic properties

TABLE 2-347 Thermodynamic Properties of Saturated Sulfur Hexafluoride (SF ) ... 

The values in these tables were generated from the NIST REFPROP software (Lemmon, E. W., McLinden, M. O., and Huber, M. L., NIST Standard Reference Database 23 Reference Fluid Thermodynamic and Transport Properties—REFPROP, National Institute of Standards and Technology, Standard Reference Data Program, Gaithersburg, Md., 2002, Version 7.1). The primary source for the thermodynamic properties is de Reuck, K. M., Craven, R. J. B., and Cole, W. A., Report on the Development of an Equation of State for Sulphur Hexafluoride, lUPAC Thermodynamic Tables Project Centre, London, 1991. Validated equations for the viscosity and thermal conductivity are not currently available for this fluid. 

HA/SET] O Flare, P. A. G., Settle, J. L., Hubbard, W. N., Fluorine bomb calorimetry. Part 14. Enthalpies of formation of the hexafluorides of sulphur, selenium, and tellurium and their thermodynamic properties to 1500°K, Trans. Faraday Soc., 62, (1966), 558-565. Cited on page 164. 

Strothmann, B. Fischer, K. Gmehling, J. Measurement of thermodynamic properties for the system sulfur hexafluoride +... 

Guder, C., and Wagner, W, A Reference Equation of State for the Thermodynamic Properties of Sulfur Hexafluoride (SF ) for Temperatures from the Melting Line to 625 K and Pressures up to 150 MPa,. Phys. Chem. Ref. Data 38, 33, 2009. 

Recently, in the Thermodynamic Data Center of Moscow Power Institute, a database on thermodynamic properties of gaseous and vapor-liquid binary mixtures was created on the basis of results of experimental investigations carried out in this institute. Freons of the methane series, carbon dioxide and sulphur hexafluoride are the first component of these mixtures, with nitrogen, hydrogen and helium as the second component. The corresponding software product was developed for the information system (Baibuz 1990). 

Chemica.1 Properties. With few exceptions, SF is chemically inert at ambient temperature and atmospheric pressure. Thermodynamically SF is unstable and should react with many materials, including water, but these reactions are kineticaHy impeded by the fluorine shielding the sulfur. Sulfur hexafluoride does not react with alkah hydroxides, ammonia, or strong acids. 

Suppose you have a system you want to describe thermodynamically. How do you do it Perhaps most important in your description is what s in the system that is, the components of the system. For our purposes, a component is defined as a unique chemical substance that has definite properties. For example, a system composed of pure UFg has a single chemical component uranium hexafluoride. Granted, UFg is composed of two elements, uranium and fluorine, but each element lost its individual identity when the compound UFg was formed. The phrase chemically homogeneous can be used to describe single-component systems. 

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