Fluid properties simulation challenge Recommendation for problem I(b): vapor-liquid equilibria for nitroethane(1) + propylene glycol monomethyl ether(2)

Fluid Phase Equilibria 217 (2004) 21–23

Extended Abstract

Fluid properties simulation challenge Recommendation for problem I(b): vapor–liquid equilibria for nitroethane(1) + propylene glycol monomethyl ether(2) J.D. Olson a,∗ , D.J. Frurip b a

The Dow Chemical Company, Analytical Sciences, Thermal Group, Bldg. 740, South Charleston, WV 25303, USA b The Dow Chemical Company, Analytical Sciences, Thermal Group, Bldg. 1897F, Midland, MI 48667, USA Received 24 March 2003; accepted 15 May 2003

This paper presents details of the determination of the recommended values used in the judging of problem 1(b) from the first Industrial Fluids Simulation Challenge. Problem conditions

(1) Azeotropic/Px data at 353.15 K x1 = azeotrope, 0.2, 0.5

(2) Azeotropic/Px data at 313.15 K x1 = azeotrope, 0.2, 0.5

Recommended values

x1

P (kPa)

x1

P (kPa)

0.2 0.5

29.36 ± 0.06 33.54 ± 0.06

0.2 0.5

4.92 ± 0.03 5.96 ± 0.03

0.765 ± 0.045

34.72 ± 0.05

0.825 ± 0.045

6.34 ± 0.05

Azeotrope

Primary source of recommendation: The values given above were calculated from a Barker’s method least-squares fit [1] to the data measured by Giles and Wilson [2]. Justification for recommendation: These are the only Px data available for this system at 353.15 and 313.15 K. The data, shown in Figs. 1 and 2 and tabulated in Tables 1 and 2, were determined from direct laboratory measurements using a well-established static total vapor pressure procedure [3]. This method measures the total pressure of the mixture in a sealed system at equilibrium after complete degassing.

∗

Corresponding author. Tel.: +1-304-747-5789. E-mail address: [email protected] (J.D. Olson).

0378-3812/$ – see front matter © 2003 Published by Elsevier B.V. doi:10.1016/j.fluid.2003.05.007

Table 1 Total pressure vs. composition data at 353.13 K for the nitroethane(1)– propylene glycol monomethylether(2) system x1

P (kPa)

0.0000 0.0498 0.0981 0.1991 0.2959 0.4044 0.4185 0.4745 0.5090 0.5614 0.5953 0.6887 0.7417 0.7960 0.8474 0.8988 0.9319 1.0000

24.18 25.70 27.02 29.35 31.08 32.61 32.72 33.30 33.60 33.97 34.22 34.59 34.79 34.75 34.61 34.31 33.86 33.11

Experimental data from (2).

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J.D. Olson, D.J. Frurip / Fluid Phase Equilibria 217 (2004) 21–23

Fig. 1. A plot of the total pressure vs. composition data at 353.13 K for the nitroethane(1)–propylene glycol monomethylether(2) system. Experimental data from (2).

Fig. 2. A plot of the total pressure vs. composition data at 313.13 K for the nitroethane(1)–propylene glycol monomethylether(2) system. Experimental data from (2).

Determination of uncertainty: The uncertainties of the derived pressure were determined from: (1) the experimental uncertainty levels in the temperature, pressure, and composition measurements reported by

Giles and Wilson, and (2) the least-squares fitting uncertainty using a three-parameter Redlich–Kister activity coefficient model. The rms errors in pressure for the Barker’s method fit were 0.05 kPa (0.16%) at 353.15 and 0.03 kPa (0.54%) at 313.15 K.

J.D. Olson, D.J. Frurip / Fluid Phase Equilibria 217 (2004) 21–23 Table 2 Total pressure vs. composition data at 313.13 K for the nitroethane(1)– propylene glycol monomethylether(2) system x1

P (kPa)

0.0000 0.0498 0.0981 0.1991 0.2959 0.4044 0.4185 0.4745 0.5090 0.5614 0.5953 0.6887 0.7417 0.7960 0.8474 0.8988 0.9319 1.0000

3.614 3.998 4.336 4.921 5.360 5.708 5.789 5.942 5.965 6.065 6.147 6.270 6.339 6.335 6.306 6.241 6.186 6.097

Experimental data from (2).

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List of symbols P pressure Px pressure as a function of mole fraction x xi mole fraction of component i Acknowledgements The authors gratefully acknowledge the AIChE DIPPR organization (specifically George Thomson and John Cunningham) for arranging for the use of unpublished VLE data in this contest. References [1] J.M. Prausnitz, R.N. Lichtenthhaler, E.G. de Azevedor, Molecular Thermodynamics of Fluid-Phase Equilibria, third ed., Upper Saddle River, Prentice Hall, New Jersey, 1999, pp. 236–242. [2] N.F. Giles, G.M. Wilson, Vapor–Liquid Equilibria of Nitroethane + Propylene Glycol Monomethyl Ether, Unpublished DIPPR Project 805/99 Report (1999). [3] N.F. Giles, G.M. Wilson, J. Chem. Eng. Data 45 (2000) 146.