Ethanol thermodynamic properties

R. C. Pemberton and C. J. Mash. "Thermodynamic Properties of Aqueous Non-Electrolyte Mixtures II. Vapour Pressures and Excess Gibbs Energies for Water-)- Ethanol at 303.15 to... 

Anhydrous copper(II) sulfate, 7 773 Anhydrous ethanol, production by azeotropic extraction, 8 809, 817 Anhydrous gaseous hydrogen sulfide, 23 633 Anhydrous hydrazine, 13 562, 585 acid-base reactions of, 13 567-568 explosive limits of, 13 566t formation of, 13 579 vapor pressures of, 13 564 Anhydrous hydrogen chloride, 13 809-813 physical and thermodynamic properties of, 13 809-813 purification of, 13 824-825 reactions of, 13 818-821 uses for, 13 833-834... 

The choice of a given database as source of auxiliary values may not be straightforward, even for a thermochemist. Consistency is a very important criterion, but factors such as the publication year, the assignment of an uncertainty to each value, and even the scientific reputation of the authors or the origin of the database matter. For instance, it would not be sensible to use the old NBS Circular 500 [22] when the NBS Tables of Chemical Thermodynamic Properties [17], published in 1982, is available. If we need a value for the standard enthalpy of formation of an organic compound, such as ethanol, we will probably prefer Pedley s Thermodynamic Data and Structures of Organic Compounds [15], published in 1994, which reports the error bars. Finally, if we are looking for the standard enthalpy of formation of any particular substance, we should first check whether it is included in CODATA Key Values for Thermodynamics [16] or in the very recent Active Thermochemical Tables [23,24],... 

Martinez, R., Gonzalez, J.A., de la Fuenta, LG., and Cobos, J.C. Thermodynamic properties of n-alkoxyethanols + organic solvent mixtures. XIV. Liquid-liquid equilibria of systems containing 2-(2-ethoxyethoxy)ethanol and selected alkanes. J. Chem. Eng. Data, 45(6) 1036-1039, 2000. 

Kolbe, B. and Gmehling, J., Thermodynamic properties of ethanol + water, II. Potentials and limits of G models. Fluid Phase Equilibria, 23 (1985) 227-242. 

We have made a quantitative investigation of the spectra of methanol, ethanol and 6-butanol over rather wide temperature and concentration ranges ( —15° to + 60°C, and 0 005 to 1 M) in order to obtain more precise information as to the spectral and thermodynamic properties of the alcohol systems. We are particularly interested in establishing such properties for a single specific species, the dimer. 

Pemberton R.C., Mash C.J., "Thermodynamic properties of aqueous nonelectrolyte mixtures II. Vapour pressures and excess Gibbs energies for water + ethanol at 303.15 K to 363.15 K determined by an accurate static method"., J. Chem. Therm., 1978, 10, 867-88. 

The physical properties of 1,2,4-oxadiazoles are unexceptional. The boiling point of the parent compound is 87 °C, within the the normal range of other two-carbon compounds. The heats of vaporization of the first three homologs (39.5-42 kJ moF1) are comparable to that of ethanol. Thermodynamic functions have been calculated over the range... 

The free energy term, 8AGtI, is obtained with relative ease from Henry s law constants. Thus, complete dissection of the effect of solvent on the various thermodynamic properties is possible in favourable cases. This was in fact achieved by Arnett et al. (1965) for the solvolysis of t-butyl chloride in aqueous ethanol mixtures and revealed that the peculiar rate variation with changing solvent composition was largely caused by changes in the initial state interactions. 

The only remaining undetermined thermodynamic properties are yH 0 and yEtQn Because or the highly nonideal behavior of a liquid solution of ethanol and wat these must be determined from experimental data. The required data, found fro VLE measurements, are given by Otsuki and Williams.t From their results for t ethanol/water system one can estimate values of yH2G and yEt0H at 200°C, (Pressu has little effect on the activity coefficients of liquids.)... 

Figure 4.3 Plots of transformed thermodynamic properties for the reaction ethanol + nadox = acetaldehyde + nadred as a function of pH at 0.25 M ionic strength and temperatures of 273.15, 298.15, and 313.15 K.

They are used as industrial solvents for small- and large-scale separation processes, and they have unusual thermodynamic properties, which depend in a complicated manner on composition, pressure, and temperature for example, the excess molar enthalpy (fp-) of ethanol + water mixture against concentration exhibits three extrema in its dependence on composition at 333.15 K and 0.4 MPa. The thermodynamic behavior of these systems is particularly intricate in the water-rich region, as illustrated by the dependencies of the molar heat capacity and partial molar volume on composition. This sensitivity of the partial molar properties indicates that structural changes occur in the water-rich region of these mixtures. Of course, the unique structural properties of water are responsible for this behavior. ... 

Pemberton, R. C. Thermodynamic properties of aqueous nonelectrolytes mixtures. Vapor pressures for the system water -I- ethanol 303.15— 363.15 K determined by an accurate static method. Conf. Int. Thermodyn. Chim. Montpellier 1975, 6, 137-144. 

The results established in the preceding paragraph may be verified by comparing the thermodynamic properties and the spectroscopic properties of associated solutions. Let us consider, for example, a solution of ethanol in carbon tetrachloride. The valency vibration of the OH group gives rise to two distinct infra-red absorption bands depending upon whether the OH group is in a monomer or in an associated complex. The fraction of molecules of alcohol which remain in the monomeric state can therefore be determined from measurements... 

The values in these tables were generated from the NIST REFPROP software (Lemmon, E. W., McLinden, M.O., and Huber, M.L., NIST Standard Reference Database 23 Reference Fluid Thermodynamic and Transport Properties—REFPROP, National Institute of Standards and Technology, Standard Reference Data Program, Gaithersburg, Md., 2002, Version 7.1). The primary source for the thermodynamic properties is Dillon, H. E., and Penoncello, S. G., A Fundamental Equation for Calculation of the Thermodynamic Properties of Ethanol, Int. J. Thermophys., 25(2) 321-335,2004. The source for viscosity is Kiselev, S. B., Ely, J. E, Abdulagatov, I. M., and Huber, M. L., Generalized SAFT-DFT/DMT Model for the Thermodynamic, Interfacial, and Transport Properties of Associating Fluids Application for n-Alkmols, Ind. Eng. Chem. Res., 44 6916-6927, 2005. The source for thermal conductivity is unpublished, 2004 however, the fit uses functional form found in Marsh, K., Perkins, R., and Ramires, M.L.V, Measurement and Correlation of the Thermal Conductivity of Propane from 86 to 600 K at Pressures to 70 MPa, J. Chem. Eng. Data, 47(4) 932-940, 2002. 

A.17.2 According to Table 18.6, each amino acid has a different AG of transfer and glycine is set to zero for convenience. Multiplication is all that s required to approximate the answers to these questions, assuming that the three amino acids have similar thermodynamic properties to their individual components. Serines 3 x (-1.3 J mol deg ) = -3.9 J moG deg . Phenylalanines = 3 x (10.5 J mol deg ) = 31.5 J mol deg The phenylalanine peptide is more hydrophobic because its AGf from ethanol to water more positive, suggesting it energetically prefers to be in ethanol compared to water. 

The values in these tables were generated from the NIST REFPROP software (Lemmon, E. W., McLinden, M.O., and Huber, M.L., NIST Standard Reference Database 23 Reference Fluid Thermodynamic and Transport Properties—REFPROP, National Institute of Standards and Technology, Standard Reference Data Program, Gaithersburg, Md., 2002, Version 7.1). The primary source for the thermodynamic properties is Dillon, H. E., and Penoncello, S. G., A Fundamental Equation for Calculation of the Thermodynamic Properties of Ethanol, Int. J. Thermophys., 25(2) 321-335,2004. The source for viscosity is Kiselev,... 

S. cerevisiae has been transformed with the P. stipitis genes XYLl and XYL2 coding for XR and XDH, respectively [46,47,141 ]. The choice of P. stipitis as the donor organism was based on its capability to utilize NADH in the xylose reduction step. Attempts to ferment xylose to ethanol with these recombinant S. cerevisiae producing XR/XDH have resulted in low ethanol yield and considerable xylitol by-product formation. This has been ascribed to the unfavorable thermodynamic properties of the reactions [140] and the fact that the first reaction preferably consumes NADPH, whereas the second reaction exclusively produces NADH. When less NADH is consumed in the XR reaction, then less NAD" is available for the XDH reaction. If the amount of NAD+ is insufficient, xylitol is produced and excreted [133]. 

---