In this work, the modified linear isotherm regularity (LIR) equation of state parameter table is extended in order to represent volumetric behaviour of primary alkylamines. In addition, the isothermal compressibility and thermal expansion coefficient of these compounds have been predicted. To do so, we consider each of primary alkylamine as a hypothetical mixture of methyl, methylene and a primary amine functional group, in which the interaction potential of each pair is assumed to be the average effective pair potential. Then, the LIR equation of state has been extended to such a hypothetical mixture. Furthermore, three basic compounds, namely, propane, -butane, and cyclohexane are used to obtain the contribution of methyl and methylene groups in the EOS parameters, and also other appropriate compounds are used to obtain the contribution of the primary amine functional groups, such as 1-pentylamine for the contribution of ？CH2NH2 and 2-aminopentane for the contribution of groups. The calculated EOS parameters along with the modified EOS are then used to calculate the density and its derivatives for alkylamines at different pressures and temperatures. The obtained results for different properties are compared with the experimental values. 1. Introduction The thermodynamic studies are important for efficient design of chemical processes, to develop correlation and prediction methods applicable over wide temperature and pressure ranges. Among others, volumetric properties such as density and its derivatives are of great interest not only for industrial applications but also for fundamental aspects. These properties can be obtained either experimentally or by thermodynamic modeling based on the equation of state (EOS). Since experimental measurements are lengthy and costly, the amount of experimental works can be reduced if efficient thermodynamic models are used to calculate the properties at different conditions of pressure and temperature. However, equations of state which are often used to predict thermodynamic properties require pure fluid parameters as inputs. The values of such parameters are, however, not only fluid specific but also temperature dependent. To develop an EOS which is predictive, a group contribution method (GCM) can be used. This method has strong theoretical ties to statistical mechanical theory. The main idea of GCM is to reduce all the interactions existing in the system to those pertaining to the pairs of the functional groups or segments from which the molecules are built. Therefore, properties and/or EOS parameters of
References
[1]
T. Nitta, E. A. Turek, R. A. Greenkorn, and K. C. Chao, “Group contribution estimation of activity coefficients in nonideal liquid mixtures,” AIChE Journal, vol. 23, no. 2, pp. 144–160, 1977.
[2]
A. Fredenslund, R. L. Jones, and J. M. Prausnitz, “Group contribution estimation of activity coefficients in nonideal liquid mixtures,” AIChE Journal, vol. 21, no. 6, pp. 1086–1099, 1975.
[3]
N. A. Smirnova and A. I. Victorov, “Thermodynamic properties of pure fluids and solutions from the hole group-contribution model,” Fluid Phase Equilibria, vol. 34, no. 2-3, pp. 235–263, 1987.
[4]
S. Skjold-J？rgensen, “Gas solubility calculations. II. Application of a new group-contribution equation of state,” Fluid Phase Equilibria, vol. 16, no. 3, pp. 317–351, 1984.
[5]
S. Espinosa, G. M. Foco, A. Bermúdez, and T. Fornari, “Revision and extension of the group contribution equation of state to new solvent groups and higher molecular weight alkanes,” Fluid Phase Equilibria, vol. 172, no. 2, pp. 129–143, 2000.
[6]
S. Espinosa, T. Fornari, S. B. Bottini, and E. A. Brignole, “Phase equilibria in mixtures of fatty oils and derivatives with near critical fluids using the GC-EOS model,” Journal of Supercritical Fluids, vol. 23, no. 2, pp. 91–102, 2002.
[7]
A. I. Majeed and J. Wagner, “Parameters from group contributions equation and phase equilibria in light hydrocarbon systems,” Journal of American Chemical Society Symposium Series, vol. 300, pp. 452–473, 1986.
[8]
G. K. Georgeton and A. S. Teja, “A simple group contribution equation of state for fluid mixtures,” Chemical Engineering Science, vol. 44, no. 11, pp. 2703–2710, 1989.
[9]
J. D. Pults, R. A. Greenkorn, and K. C. Chao, “Chain-of-rotators group contribution equation of state,” Chemical Engineering Science, vol. 44, no. 11, pp. 2553–2564, 1989.
[10]
H. P. Gros, S. B. Bottini, and E. A. Brignole, “High pressure phase equilibrium modeling of mixtures containing associating compounds and gases,” Fluid Phase Equilibria, vol. 139, no. 1-2, pp. 75–87, 1997.
[11]
O. Ferreira, T. Fornari, E. A. Brignole, and S. B. Bottini, “Modeling of association effects in mixtures of carboxylic acids with associating and non-associating components,” Latin American Applied Research, vol. 33, no. 3, pp. 307–312, 2003.
[12]
S. Espinosa, S. Díaz, and T. Fornari, “Extension of the group contribution associating equation of state to mixtures containing phenol, aromatic acid and aromatic ether compounds,” Fluid Phase Equilibria, vol. 231, no. 2, pp. 197–210, 2005.
[13]
I. Ishizuka, E. Sarashina, Y. Arai, and S. Saito, “Group contribution model based on the hole theory,” Journal of Chemical Engineering of Japan, vol. 13, no. 2, pp. 90–97, 1980.
[14]
K. P. Yoo and C. S. Lee, “New lattice-fluid equation of state and its group contribution applications for predicting phase equilibria of mixtures,” Fluid Phase Equilibria, vol. 117, no. 1, pp. 48–54, 1996.
[15]
W. Wang, X. Liu, C. Zhong, C. H. Twu, and J. E. Coon, “Group contribution simplified hole theory equation of state for liquid polymers and solvents and their solutions,” Fluid Phase Equilibria, vol. 144, no. 1-2, pp. 23–36, 1998.
[16]
G. A. Parsafar and Z. Kalantar, “Extension of linear isotherm regularity to long chain primary, secondary and tertiary alcohols, ketones and 1-carboxylic acids by group contribution method,” Fluid Phase Equilibria, vol. 234, no. 1-2, pp. 11–21, 2005.
[17]
Y. Miyake, A. Baylaucq, F. Plantier, D. Bessières, H. Ushiki, and C. Boned, “High-pressure (up to 140？MPa) density and derivative properties of some (pentyl-, hexyl-, and heptyl-) amines between (293.15 and 353.15) K,” Journal of Chemical Thermodynamics, vol. 40, no. 5, pp. 836–845, 2008.
[18]
M. Yoshimura, A. Baylaucq, J. P. Bazile, H. Ushiki, and C. Boned, “Volumetric properties of 2-alkylamines (2-aminobutane and 2-aminooctane) at pressures up to 140？MPa and temperatures between (293.15 and 403.15) K,” Journal of Chemical and Engineering Data, vol. 54, no. 6, pp. 1702–1709, 2009.
[19]
M. Yoshimura, C. Boned, G. Galliéro, J. P. Bazile, A. Baylaucq, and H. Ushiki, “Influence of the chain length on the dynamic viscosity at high pressure of some 2-alkylamines: measurements and comparative study of some models,” Chemical Physics, vol. 369, no. 2-3, pp. 126–137, 2010.
[20]
G. Parsafar and Z. Kalantar, “Extension of linear isotherm regularity to long chain alkanes,” Iranian Journal of Chemistry and Chemical Engineering, vol. 22, no. 2, pp. 1–8, 2003.
[21]
G. Parsafar and E. A. Mason, “Linear isotherms for dense fluids: a new regularity,” Journal of Physical Chemistry, vol. 97, no. 35, pp. 9048–9053, 1993.
[22]
G. Parsafar, F. Kermanpour, and B. Najafi, “Prediction of the temperature and density dependencies of the parameters of the average effective pair potential using only the LIR equation of state,” Journal of Physical Chemistry B, vol. 103, no. 34, pp. 7287–7292, 1999.
[23]
G. Parsafar and E. A. Mason, “Linear isotherms for dense fluids: extension to mixtures,” Journal of Physical Chemistry, vol. 98, no. 7, pp. 1962–1967, 1994.
[24]
D. Papaioannou, M. Bridakis, and C. G. Panayiotou, “Excess dynamic viscosity and excess volume of n-butylamine + 1-alkanol mixtures at moderately high pressures,” Journal of Chemical and Engineering Data, vol. 38, no. 3, pp. 370–378, 1993.
