Equation Antoine

Whereas for theoretical considerations, the Clausius - Clapeyron equation plays a fundamental role, practitioners favor Antoine equation [7]. This equation is very similar to the Clausius - Clapeyron equation  

A lot of values of parameters A, B, and C have been fitted for various substances and tabulated. The temperature range of validity is carefully attached to the data. Turning to dimensionless variables, one parameter can be omitted by the condition that the reduced pressure approaches one at the reduced temperature of one p 1 f 1. Thus, Eq. (8.12) becomes 

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Compilation of vapor-pressure data for organic compounds data are correlated with the Antoine equation and graphs are presented. 

Vapor-pressure data correlated with the Antoine equation. Results displayed graphically. 

The vapor-liquid equilibrium of the binary mixture is well fitted by Van Laar s equations (228). It was determined from 100 to 760 mm Hg. and the experimental data was correlated by the Antoine equation (289, 290), with P in mm Hg and t in °C ... 

The normal boiling point of pure thiazole is 118.241 0.004°C. 2-Methylthiazole behaves similarly, fitting the Antoine equation (291) ... 

Numerous mathematical formulas relating the temperature and pressure of the gas phase in equilibrium with the condensed phase have been proposed. The Antoine equation (Eq. 1) gives good correlation with experimental values. Equation 2 is simpler and is often suitable over restricted temperature ranges. In these equations, and the derived differential coefficients for use in the Hag-genmacher and Clausius-Clapeyron equations, the p term is the vapor pressure of the compound in pounds per square inch (psi), the t term is the temperature in degrees Celsius, and the T term is the absolute temperature in kelvins (r°C -I- 273.15). 

The constants in the Antoine equation may be estimated by selecting three widely spaced data points and substituting in the following equations in sequence ... 

Antiviral drug Antivitamins Antiwear agents Antiwear treatment Anto3 "E" [61931-82-6] Anto3 "H" [101-72-4] Antoine equation... 

The Antoine equation for acetic acid has recentiy been revised (2) ... 

Many empidcal expressions have been proposed to represent the temperature dependence of the vapor—hquid saturation pressure, as shown by the vaporization curve of Figure 2. The most popular is the Antoine equation ... 

Vapor pressure as a function of the temperature is correlated by the Antoine equation ... 

Two empirical parameters are evident in equation 7, the heat of vaporization and the integration constant, I. Experimental data indicate that the linear relationship suggested by Clausius-Clapeyron may not be followed over a large temperature range (4) therefore additional adjustable parameters have been added to equation 7 to improve its correlating abiUty. The most prominent of these is the Antoine equation ... 

The equation developed by the Design Institute for Physical Property Data (DIPPR) is another successful correlating tool for vapor pressure (4). It is an empirical extension of the Antoine equation and has two additional constants, D and E ... 

Mathematical Consistency Requirements. Theoretical equations provide a method by which a data set s internal consistency can be tested or missing data can be derived from known values of related properties. The abiUty of data to fit a proven model may also provide insight into whether that data behaves correctiy and follows expected trends. For example, poor fit of vapor pressure versus temperature data to a generally accepted correlating equation could indicate systematic data error or bias. A simple sermlogarithmic form, (eg, the Antoine equation, eq. 8), has been shown to apply to most organic Hquids, so substantial deviation from this model might indicate a problem. Many other simple thermodynamics relations can provide useful data tests (1—5,18,21). 

A nonlinear model would involve one or more of the coefficients in nonlinear form such as the Antoine equation (eq. 8) or... 

The Antoine equation does not fit data accurately much above the normal boiling point. Thus, as regression by computer is now standard, more accurate expressions applicable to the critical point have become usable. The entire DIPPR Compilation" is regressed with the modified RiedeP equation (2-28) with constants available for over 1500 compounds. 

The Antoine equation, which is more satisfactory for general use, has the form... 

Abstracted from Gmehling and Onken, Vapor-Liquid Kquilihhum Data Collection, DECHEMA Chemistry Data ser., vol. 1 (parts 1-10), Frankfurt, 1977. f Antoine equation is log P = A — B/(T + C) with P " in torr and T in C. 

The dependence of the saturation pressure / s and temperature Ts for several liquids is determined by the Antoine equation (Reid et al. 1987). We use the following expression for saturation pressure of the water (Seaver et al. 1989) ... 

The jacket steam pressure, Pj, is itself a function of the jacket steam temperature, Tj, as listed in steam tables or as correlated by the Antoine equation for vapour pressure, where... 

As boiling proceeds, the loss of the lightest organic vapours will cause the boiling point to increase with time. The vapour pressures Pj and P of the pure components can be calculated using the Antoine equation... 

Aerated tank with oxygen electrode 534 Agitated extraction column 556 Ammonia 567 Antoine equation 137 Area... 

The vapour pressures of the pure liquids can be calculated from the Antoine equation (see Chapter 8) ... 

Several equations have been developed to express vapour pressure as a function of temperature. One of the most commonly used is the three-term Antoine equation, Antoine (1888) ... 

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