Freon, properties

Tomanovskaya V. F., Kolotova B. E. Freons, Properties and Application. Khimiya, Moscow, 1970. 

The catalyst is formed by reaction of HF on SbClj. The Freons have a unique combination of properties which make them ideally suited for use as refrigerants and aerosol propellants. They have low bp, low viscosity, low surface tension and high density, and are non-toxic, non-flammable, odourless, chemically inert and thermally stable. The most commonly used is CF2CI2, bp, —29.8°. The market for Freons... 

Fractional crystallization, 413 Freezing point lowering, 325, 393 Freon, 362 Frequency of light, 246 relation to wave length, 251 Fructose, 423 Fumaric acid, 428 properties, 308 structure, 316... 

Set no. Properties assumed important in addition to A, pL, and pv Implied scaling factors for water and Freon ... 

Most of the tests made so far have used water and Freon-12 (CC12F2), and the scaling factors implied by the various possible sets of scaling laws may be calculated from the physical properties for these two fluids. The appropriate scaling factors based on water at 1000 psia, for which pL/pv = 20.63, are listed in Table VII. As an example of how the scaling factors are calculated, the group Ahjl in Eq. (39) will have the same value for water and Freon-12 if... 

It is noted that additional scales for the property index are shown in Figure 3.42 to correspond to liquid metals as well as water and Freon-22 at different temperatures, indicating the applicability of the correlation to other fluids. 

Figure 5.32 Comparison of derived thermodynamic properties (water and Freon-12). (From May-inger, 1981. Copyright 1981 by Hemisphere Publishing Corp., New York. Reprinted with permission.)...

Here, we focus on one class ofblock copolymers synthesized by this method polystyrene-6-poly(vinylperfluorooctanic acid ester) block copolymers (Figure 10.33). After describing the synthesis and characterization, we will treat some properties and the potential applications of this new class ofblock copolymers. The amphiphilicity of the polymers is visualized by the ability to form micelles in diverse solvents that are characterized by dynamic light scattering (DLS). Then the use of these macromolecules for dispersion polymerization in very unpolar media is demonstrated by the polymerization of styrene in 1,1,2-trichlorotrifluoroethane (Freon 113). 

It is desired to find a replacement for Freon-12 as an alternative refrigerant [Duvedi Achenie (1996)]. The objective is to find replacements that have the same refrigerant related properties as Freon-12 but without the harmfull environmental properties (such as the Ozone depletion potential) - The new refrigerant must absorb heat at temperatures as low as -1.1°C and reject heat at temperatures as high as 313 K. It must also respect the following characteristics ... 

Altunin, V. V., V. Z. Geller, E. K. Petrov, D. C. Rasskazov, and G. A. Spiridonov, THERMOPHYSICAL PROPERTIES OF FREONS. Methane Series, Part 1, Hemisphere Publishing Corporation, New York, NY (1987). 

Finally, a third formulation was devised which excluded the use of Freon 11 In the polyol component. Freon 11 was placed In the Isocyanate component and both Isocyanate and polyol components were changed to meet viscosity considerations. Subsequent aging studies showed the Isocyanate to age similarly to the previously aged (Formulation 2) Isocyanate. The polyol showed virtually no Increase In acid number at any aging temperature over 13 months. Thus, at ambient temperature we would expect a 6-8 year system lifetime on the Isocyanate before a 10% change In analytical properties would dictate a material change-out. The polyol appears to have a greater lifetime, but would probably be replaced at the same time. 

The role of CFCs in the destruction of ozone in the stratosphere was something of a surprise to some researchers because those compounds are normally quite stable. In fact, their stability is one of their most desirable properties for many industrial and commercial applications. But, when CFCs escape into the atmosphere and drift upward, they are exposed to ultraviolet radiation in sunlight and, as is oxygen itself, are dissociated by that radiation. In the case of Freon-12 (CCI2F2), photodissociation results in the formation of free chlorine atoms ... 

The term oil and grease refers to a broad class of organic substances recovered from the sample matrices by extraction with an appropriate solvent. Such recovery, therefore, is characteristic of certain physical properties of the compounds, primarily the volatility of the compounds and their solubility in the extraction solvent. The solvent must be immiscible in water and volatile, as well as readily distilled on a water bath. Many solvents or mixed-solvent systems should be suitable for the extraction of oil and grease in aqueous and nonaqueous samples. These include petroleum ether, w-hexanc, methylene chloride, methyl ter/-butyl ether, and trichlorotrifhroroethan (freon). These solvents are listed in Table 1. 

In the interest of conserving space in this handbook, a compact tabular presentation format has been adopted. Table 5.1.5.1 lists the chemical name, and its freon number (if applicable), molecular formula, molar weight and melting and boiling points. These data are available for virtually all substances in this group. Also shown in this table is the availability, expressed as a tick mark, of data on vapor pressure, solubility in water, octanol-water partition coefficient (Kqw) and the second order reaction rate constant with hydroxyl radicals. This rate constant is the critical determinant of persistence in the atmosphere. Tables 5.1.5.2 to Table 5.1.5.5 list the compounds and give the available property data with citations. 

Du Pont (1969) Freon Fluorocarbons Properties and Applications. Technical Bulletin B-2. Du Pont de Nemours Company, Wilmington, Delaware. 

Leu, A.-D., Robinson, D.B. (1992) High-pressure vapor-liquid equilibrium phase properties of the octafluoropropane (K-218)-chlorodifluoromethane (Freon-22) binary system. J. Chem. Eng. Data 37, 7-10. 

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