Pressure-temperature data

Calculated from density-pressure-temperature data in Vukalovitcb and Altunin, Theimophysical Fropeities of Carhon Dioxide, Atomizdat, Moscow, 1965, and Collet s, London, 1968, translation. 

Table 1.5. Typical Flange Pressure-Temperature Data...

Dreisbach, R.R., Shrader, A.A.I. (1949) Vapor pressure-temperature data on some organic compounds. Ind. Eng. Chem. 41, 2879-2880. 

The average dT/dt is typically an arithmetic average between the value at set pressure and the value at peak allowed pressure. The properties Cp, hfg, i, either can be evaluated at the set conditions or can be taken as the average values between the set condition and the peak allowed pressure condition. Alternatively, the term h/g/t)/g in Eq. (23-95) can be replaced by T(dP/dT)tat via the Clapeyron relation. This holds reasonably well for a multicomponent system of near constant volatility. Such an application permits direct use of the experimental pressure-temperature data obtained from a closed-system runaway VSP2 test. This form of Eq. (23-95) has been used to demonstrate the advantageous reduction in both vent rate and vent area with allowable overpressure (Leung, 1986a). 

The next part is messy, but somebody s got to do it. I m going to use the vapor pressure-temperature data for the normal boiling points of both liquids in the Clausius-Clapyron equation. Why They re convenient, known vapor pressure-temperature points. When I do this, though, I exercise my right to use different superscripts to impress upon you that these points are the normal boiling points. So for liquid A, we have p and TJ if A is isobutyl alcohol,pi = 760 torr and T K = 101.8°C. For liquid B, we havep and T5 if B is isopropyl alcohol, p = 760 torr and T% = 82.3 °C. 

The enthalpy of vaporization was calculated by the method of Reference 4 from the vapor pressure-temperature data found in D. R. Stull, Ind. Eng. Chem., 39, 517 (1947) cited from Hein and Schramm, Z. Physik. Chem., 86, 385 (1914). 

The vapor pressure of a liquid increases with increasing temperature. Reviews on and discussion of different types of vapor pressure-temperature functions can be found in the literature [17-20]. The most common representation of vapor pressure-temperature data for a pressure interval of about 10 to 1500 mmHg [1] is the three-parametric Antoine equation ... 

Methods Based on the Frost-Kalkwarf Equation The Frost-Kalkwarf equation relies on four compound-specific coefficients to correlate vapor pressure-temperature data ... 

Na (g). We have calculated the heat of sublimation of sodium to form the monatomic gas from the vapor pressure-temperature data, taking due account of the appreciable amount of Na2 molecules contained in the actual vapor at equilibrium. The vapor pressure data used are those of Edmonson and Egerton,1-2 Rodebush and Walters,1 Rodebush,2 Rodebush and de Vries,1 Rodebush and Henry,1 Haber and Zisch,1 Ladenberg and Minkowski,1 and Gibhart.1 See also Kroner,1 Hackspill,1 van Laar,9 and Simon and Zeidler.1 Our value for the heat of sublimation, Na (c) = Na (g), is —25.9 at 18°. Sherman1 calculated —25.8. 

After 1900 the direct determination of hydrate number was abandoned in favor of the second, indirect method. The indirect method is still in use today and is based on calculation of the enthalpies of formation of hydrate from gas and water, and from gas and ice. This method was originally proposed by de Forcrand (1902) who used the Clapeyron equation to obtain the heat of dissociation from three-phase, pressure-temperature data, as in the below paragraph. With this more accurate method many exceptions were found to Villard s Rule. The historical summary provided in Chapter 1 indicates that while the number of hydrated water molecules was commonly thought to be an integer, frequently that integer... 

Example 4.7 Hydration Number from Pressure-Temperature Data for... 

Thermodynamic data form the basis for future theoretical developments, because the data represent the physical reality and they have been painstakingly obtained. Usually a period of several months (or even years) is required to construct an experimental apparatus and, due to long metastable periods, it is not uncommon to obtain only one pressure-temperature data point per 1 or 2 days of experimental effort. Phase equilibria data are presented in Section 6.3.1 for simple hydrates (Section 6.3.1.1), binary (Section 6.3.1.2), ternary (Section 6.3.1.3),... 

In a thorough review of calorimetric studies of clathrates and inclusion compounds, Parsonage and Staveley (1984) presented no direct calorimetric methods used for natural gas hydrate measurements. Instead, the heat of dissociation has been indirectly determined via the Clapeyron equation by differentiation of three-phase equilibrium pressure-temperature data. This technique is presented in detail in Section 4.6.1. 

The present paper gives an overview of results on high-pressure phase equilibria in the ternary system carbon dioxide-water-1-propanol, which has been investigated at temperatures between 288 and 333 K and pressures up to 16 MPa. Furthermore, pressure-temperature data on critical lines, which bound the region where multiphase equilibria are oberserved were taken. This study continues the series of previous investigations on ternary systems with the polar solvents acetone [2], isopropanol [3] and propionic add [4], A classification of the different types of phase behaviour and thermodynamic methods to model the complex phase behaviour with cubic equations of state are discussed. 

Pressure-temperature diagrams offer a useful way to depict the phase behaviour of multicomponent systems in a very condensed form. Here, they will be used to classify the phase behaviour of systems carbon dioxide-water-polar solvent, when the solvent is completely miscible with water. Unfortunately, pressure-temperature data on ternary critical points of these systems are scarcely published. Efremova and Shvarts [6,7] reported on results for such systems with methanol and ethanol as polar solvent, Wendland et al. [2,3] investigated such systems with acetone and isopropanol and Adrian et al. [4] measured critical points and phase equilibria of carbon dioxide-water-propionic acid. In addition, this work reports on the system with 1-propanol. The results can be classified into two groups. In systems behaving as described by pattern I, no four-phase equilibria are observed, whereas systems showing four-phase equilibria are designated by pattern II (cf. Figure 3). 

Dreisbach, R.R., Shrader, A.A.I. (1949) Vapor pressure-temperature data on some organic compounds. Ind. Eng. Chem. 41,2879-2880. Eadsforth, C.V. (1986) Application of reverse-phase HPLC for the determination of partition coefficients. Pest. Sci. 17(3), 311-325. Edney, E.O., Corse, E.W. (1986) Validation of OH Radical Reaction Rate Constant Test Protocol. NTIS PB86-166 758/as. U.S. Environmental Protection Agency, Washington, D.C. 

A relatively simple empirical equation that correlates vapor pressure-temperature data extremely well is the Antoine equation... 

Equation (288) results in a straight line when P is plotted against T, which fits the experimental pressure-temperature data usually obtained during melting of solids or freezing of liquids. 

Ind. Eng. Chem.9 1923, 15, 592 Calingaert and Davis, ibid., 1925,17, 1287 Hougen and Watson, Industrial Chemical Calculations, 1931, 95 Wheeler, Phil. Mag., 1931, 11, 441 Germann and Knight, Line Co-ordinate Charts for Vapor Pressure-Temperature Data, Boulder, Colorado, 1934 (b.p. corrections for pressure) Ind. Eng. Chem., 1934, 26, 467 Lippincott and Lyman, ibid., 1946, 38, 320 Dreisbach and Schrader, ibid., 1949, 41, 2879. 

Table III. Pressure-Temperature Data for Solid Californium T(K) P (atm) 3rd-law AH qft ...

Dreisbach, R. R. (1952) Pressure-Volume-Temperature Relationships of Organic Compounds, 3rd edn. Handbook Publishers. Contains Cox chart constants and tables of pressure-temperature data for individual compounds. 

Table 4.4 Pressure-temperature data for the decomposition of di-/-butyl peroxide...

R. R. Dreisbach, Vapour Pressure-Temperature Data for Organic Compounds , The Dow Chemical Company, Midland, Michigan, 2nd ed., 1946. 

Cox chart constants and tables of vapour pressure-temperature data for individual compounds. 

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