Lydersen method

The Lydersen method is a group contribution method for the estimation of critical properties temperature (Tc), pressure (Pc) and volume (Vc). The method is named after Aksel Lydersen who published it in 1955.[1] The Lydersen method is the prototype for and ancestor of many new models like Joback,[2] Klincewicz,[3] Ambrose,[4] Gani-Constantinou[5] and others.

The Lydersen method is based in case of the critical temperature on the Guldberg rule which establishes a relation between the normal boiling point and the critical temperature.

Equations

Critical temperature

Guldberg has found that a rough estimate of the normal boiling point Tb, when expressed in kelvins (i.e., as an absolute temperature), is approximately two-thirds of the critical temperature Tc. Lydersen uses this basic idea but calculates more accurate values.

Critical pressure

Critical volume

M is the molar mass and Gi are the group contributions (different for all three properties) for functional groups of a molecule.

Group contributions

Group Gi (Tc) Gi (Pc) Gi (Vc) Group Gi (Tc) Gi (Pc) Gi (Vc)
-CH3,-CH2-0.0200.22755.0 >CH0.0120.21051.0
-C<-0,21041.0 =CH2,#CH0.0180,19845.0
=C<,=C=-0.19836.0 =C-H,#C-0.0050.15336.0
-CH2-(Ring)0.0130.18444.5 >CH-(Ring)0.0120.19246.0
>C<(Ring)-0.0070.15431.0 =CH-,=C<,=C=(Ring)0.0110.15437.0
-F0.0180.22418.0 -Cl0.0170.32049.0
-Br0.0100.50070.0 -I0.0120.83095.0
-OH0.0820.06018.0 -OH(Aromat)0.031-0.0203.0
-O-0.0210.16020.0 -O-(Ring)0.0140.1208.0
>C=O0.0400.29060.0 >C=O(Ring)0.0330.20050.0
HC=O-0.0480.33073.0 -COOH0.0850.40080.0
-COO-0.0470.47080.0 -NH20.0310.09528.0
>NH0.0310.13537.0 >NH(Ring)0.0240.09027.0
>N0.0140.17042.0 >N-(Ring)0.0070.13032.0
-CN0.0600.36080.0 -NO20.0550.42078.0
-SH,-S-0.0150.27055.0 -S-(Ring)0.0080.24045.0
=S0.0030.24047.0 >Si<0.0300.540-
-B<0.030--

Example calculation

Acetone is fragmented in two different groups, one carbonyl group and two methyl groups. For the critical volume the following calculation results:

Vc = 40 + 60.0 + 2 * 55.0 = 210 cm3

In the literature (such as in the Dortmund Data Bank) the values 215.90 cm3,[6] 230.5 cm3 [7] and 209.0 cm3 [8] are published.

References

  1. Lydersen, a.L. "Estimation of Critical Properties of Organic Compounds". Engineering Experiment Station Report. 3. Madison, Wisconsin: University of Wisconsin College Engineering.
  2. Joback, K.G.; Reid, R.C. (1987). "Estimation of pure-component properties from group-contributions". Chemical Engineering Communications. 57 (1–6). Informa UK Limited: 233–243. doi:10.1080/00986448708960487. ISSN 0098-6445.
  3. Klincewicz, K. M.; Reid, R. C. (1984). "Estimation of critical properties with group contribution methods". AIChE Journal. 30 (1). Wiley: 137–142. Bibcode:1984AIChE..30..137K. doi:10.1002/aic.690300119. ISSN 0001-1541.
  4. Ambrose, D. (1978). Correlation and Estimation of Vapour-Liquid Critical Properties. I. Critical Temperatures of Organic Compounds. National Physical Laboratory Reports Chemistry. Vol. 92. p. 1-35.
  5. Constantinou, Leonidas; Gani, Rafiqul (1994). "New group contribution method for estimating properties of pure compounds". AIChE Journal. 40 (10). Wiley: 1697–1710. Bibcode:1994AIChE..40.1697C. doi:10.1002/aic.690401011. ISSN 0001-1541.
  6. Campbell, A. N.; Chatterjee, R. M. (1969-10-15). "The critical constants and orthobaric densities of acetone, chloroform, benzene, and carbon tetrachloride". Canadian Journal of Chemistry. 47 (20). Canadian Science Publishing: 3893–3898. doi:10.1139/v69-646. ISSN 0008-4042.
  7. Herz, W.; Neukirch, E. (1923). "Zur Kenntnis kritischer Grössen". Zeitschrift für Physikalische Chemie. 104: S.433-450. doi:10.1515/zpch-1923-10429. S2CID 99833350.
  8. Kobe, Kenneth A.; Crawford, Horace R.; Stephenson, Robert W. (1955). "Industrial Design Data—Critical Properties and Vapor Presesures of Some Ketones". Industrial & Engineering Chemistry. 47 (9). American Chemical Society (ACS): 1767–1772. doi:10.1021/ie50549a025. ISSN 0019-7866.
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