Models for Estimation of Pure n-Alkanes' Thermodynamic Properties as a Function of Carbon Chain Length

Abstract

Simple predictive relationships for the estimation of pure normal alkanes' thermodynamic properties, like transition temperatures, phase change enthalpies, and heat capacities in the solid or liquid state, are established as a function of carbon atom number n c , by combining our own calorimetric experimental results and a general review of literature data. This study underlines that total and melting enthalpies vary linearly with n c carbon atom number, whatever the parity of n c , while order-disorder transition enthalpies show a quadratic variation and an alternating effect between odd-and even-numbered n-alkanes. Heat capacity variations versus temperature and the carbon chain length were represented by a model of group contributions for the liquid phase and by an expression derived from Einstein's model for the solid state.

Heat capacity prediction for polynuclear aromatic solids using vibration spectra

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High pressure phase equilibria in methane+waxy systems

“…3. Additionally, as pure heptadecane presents one solid-solid phase transition few Kelvin below the melting temperatures [15], both liquid-solid and solid-solid equilibrium lines [16] of n-heptadecane were added in Fig. 3 in order to display the full projection of the binary system phase behaviour in the pressure-temperature range of interest.…”

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“…Williams, 1997;Briard et al, 2003), organometallic compounds (e.g. Nikitin et al, 2010) and also for mixtures (e.g.…”