Vapor pressure correlations for

Mackay, D., Bobra, A. M., Chan, D. W., Shiu, W.-Y. (1982) Vapor pressure correlation for low-volatility environmental chemicals. Environ. Sci. Technol. 16, 645-649. 

Table 8.4 Parameters of vapor-pressure correlation for components.

Mackay D, Bobra AM, Chan D, Shiu WY. Vapor pressure correlations for low volatility environmental chemicals. Environ Sci Technol 1982 16 645-9. 

PRSV equation for the substances considered here are given in Table 3.1.1 k of the PRSV equation is obtained by fitting pure component saturation pressure (P p) versus temperature data, A computer program to optimize k for a set of T versus / P data is provided on the diskette accompanying this monograph, and the program details are presented in Appendix D. The effect of this parameter on the accuracy of vapor pressure correlations for several fluids is shown in Figure 3.1.1. 

The flrst approach is simple correlations of properties. This is most convenient when the property of interest is a fnnction of only one variable, such as the vapor pressure (a function of temperature only). Snch correlations can also be useful for properties of liquids (as long as they are not close to the critical point), since most liquid-phase properties are relatively insensitive to pressure and can be approximately represented as a function of temperatnre only. Several databases [11-14] contain correlations for pure-flnid properties as a function of temperature for many common snbstances, and vapor-pressure correlations for many substances are in some additional sources [5, 15]. It is important to be aware of the range of conditions in which a correlation has been fltted, as extrapolation can lead to significant errors. 

Vapor pressure correlations for pure contaminants were derived from Praiy and Green (1997). 

A large acentric factor doesn t make sense physically but is used to correlate vapor pressures for the petroleum fractions. Perhaps a vapor pressure correlation for petroleum fractions could supplant the use of acentric factor. 

Correlation and compilation of vapor-pressure data for pure fluids. Normal and low pressure region. 

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

The correlations were generated by first choosing from the literature the best sets of vapor-pressure data for each fluid. 

Silva and Weber (1993) reported vapor pressure measurements for the 1-ch oro-l,l-Difluoroethane (RI42b) and 1,1 -Difluoroethane (R152a) refrigerants. The data are given in Tables 3.5 and 3.6 respectively. Use Antoine s equation to correlate the data for R142b and the following equation for R152a (Silva and Weber, 1993)... 

Myers, H.S., Fenske, M.R. (1955) Measurement and correlation of vapor pressure data for high boiling hydrocarbons, hid. Eng. Chem. 47, 1652-1658. 

Correlating ln(Pc /Pc), with vapor pressure data For isotopomer pairs with the vapor pressure and VPIE established near Tc, a thermodynamic consistency test between ln(Tc7Tc) and ln(Pc /Pc), and calculation of ln(Pc7Pc) from ln(Tc7Tc) is possible. The critical pressure of the heavier isotopomer at its critical temperature, Pc(Tc), can be calculated from the lighter, Pc,(Tc7 provided the vapor pressure of the lighter between Tc and Tc, the VPIE, and Tc and Tc are known. For Tc < Tc ... 

Rordorf, B.F. Prediction of vapor pressures, boiling points and enthalpies of fusion for twenty-nine halogenated dibenzo-p-dioxins and fifty-five dibenzofurans by a vapor pressure correlation method. Chemosphere, 18(l-6) 783-788,1989. Rosen, J.D. and Carey, W.F. Preparation of the photoisomers of aldrin and dieldrin. 7 Agric. Food Chem., 16(3) 536-537,1968. Rosen, J.D. and Strusz, R.F. Photolysis of 3-(p-bromophenyl)-l-methoxy-l-methylurea, 7 Agric. Food Chem., 16(4) 568-573, 1968. 

Fig. 3 Correlation of soil/air concentration ratios (Q) with sub-cooled liquid vapor pressure (VPl) for 10 chlorobornane congeners or congener groups which span the volatility range in technical toxaphene [30] or a sampling event in Alabama [34]...

Rordorf, B.F. 1989. Prediction of vapor pressures, boiling points and enthalpies of fusion for twenty-nine halogenated dibenzo-p-dioxins and fifty-five dibenzofurans by a vapor pressure correlation method. Chemosphere 18 783-88. 

Figure 6.1-2 Reference-substance plot for vapor pressure correlation.

Description An expression for AH, can be obtained from Eq. (2-33) by using an appropriate vapor pressure correlation. If one differentiates the Riedel vapor pressure correlation, Eq. (2-22), in accordance with Eq. (2-33), one obtains the heat of vaporization as... 

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