Modelling thermodynamic properties of iodoalkane + alkane systems using group contribution models

2001 ◽  
Vol 3 (22) ◽  
pp. 5006 ◽  
Author(s):  
Josefa García ◽  
Enriqueta R. López ◽  
Luis Lugo ◽  
Josefa Fernández
Keyword(s):  
Thermodynamic Properties ◽  
Group Contribution

Expanding the Applications of the SAFT-γ Mie Group-Contribution Equation of State: Prediction of Thermodynamic Properties and Phase Behavior of Mixtures

2020 ◽  
Vol 65 (12) ◽  
pp. 5862-5890
Author(s):  
Andrew J. Haslam ◽  
Alfonso González-Pérez ◽  
Silvia Di Lecce ◽  
Siti H. Khalit ◽  
Felipe A. Perdomo ◽  
...  
Keyword(s):  
Equation Of State ◽  
Thermodynamic Properties ◽  
Phase Behavior ◽  
Group Contribution ◽  
State Prediction

Thermodynamic properties of binary mixtures containing ketones. VII. Analysis of the properties of n-alkanone + n-alkane, and n-alkanone + n-alkanone mixtures in terms of a quasi-chemical group contribution model

1981 ◽  
Vol 7 (2) ◽  
pp. 95-120 ◽  
Author(s):  
Henry V. Kehiaian ◽  
Jean-Pierre E. Grolier ◽  
Mohammad-Reza Kechavarz ◽  
George C. Benson ◽  
Osamu Kiyohara ◽  
...  
Keyword(s):  
Thermodynamic Properties ◽  
Binary Mixtures ◽  
Group Contribution ◽  
Group Contribution Model

Ethanol and Distillate Blends: A Thermodynamic Approach to Miscibility Issues

2010 ◽  
Author(s):  
Jean-Noe¨l Jaubert ◽  
Romain Privat ◽  
Michel Molie`re
Keyword(s):  
Liquid Phase ◽  
Thermodynamic Properties ◽  
Functional Groups ◽  
Fossil Fuels ◽  
Chemical Properties ◽  
Physical Property ◽  
Diesel Oil ◽  
Group Contribution ◽  
Heat Of Mixing ◽  
The Stability

In the recent years, the quest for an ever wider cluster of sustainable primary energies has prompted an increasing number of attempts to combine the emission sobriety of bio fuels with the energy density advantage of fossil fuels. A number of compositions incorporating hydrocarbons, ethanol and in some cases limited amounts of water have been proposed, especially in the forms of micro emulsions, with a variable success. Indeed due to markedly different physical and chemical properties, ethanol and gasoil are able to blend and form homogeneous solutions only in limited proportion ranges. Indeed, such mixtures often give rise to liquid-liquid equilibrium. A key parameter is thus the Minimum Miscibility Temperature (MMT), i.e. the temperature above which ethanol and gasoil become completely miscible. In fact, commercial gasoils do not constitute a monolithic product but display in the contrary a large span of compositions that influence the stability of these blends. In this context, the LRGP laboratory (Laboratoire Re´actions et Ge´nie des Proce´de´s) has undertaken an investigation program intended to understand the factors underlying the stability of ethanol/gasoil blends. The approach is based on the calculation of the liquid-liquid phase diagrams formed by anhydrous ethanol and a mixture of various hydrocarbons representative of the diesel oil pool using the group contribution concept. Indeed, for correlating thermodynamic properties, it is often convenient to regard a molecule as an aggregate of functional groups; as a result, some thermodynamic properties (heat of mixing, activity coefficients) can be calculated by summing group contributions. In this study, the universal quasichemical functional group activity coefficient (UNIFAC) method has been employed as it appears to be particularly useful for making reasonable estimates for the studied non ideal mixtures for which data are sparse or totally absent. In any group-contribution method, the basic idea is that whereas there are thousands of chemical compounds of interest in chemical technology, the number of functional groups that constitute these compounds is much smaller. Therefore, if we assume that a physical property of a fluid is the sum of contributions made by the molecule’s functional groups, we obtain a possible technique for correlating the properties of a very large number of fluids in terms of a much smaller number of parameters that characterize the contributions of individual groups. This paper shows the large influence exerted by the paraffinic, aromatic and naphthenic character of the gasoil but also the sulfur content of the fossil fraction on the shape of the liquid-liquid phase diagram and on the value of the minimum miscibility temperature.

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