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Journal of Thermal Analysis and Calorimetry
Authors: S. Cebreiro, M. Illobre, M. Mato, V. Verdes, J. Legido, and M. Paz Andrade

Abstract  

We have determined the excess molar enthalpies H m E at 298.15 K and normal atmospheric pressure for the binary mixtures containing tert-butyl methyl ether (MTBE)+(methanol, ethanol, 1-propanol, 1-pentanol) using a Calvet microcalorimeter.

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Abstract  

Excess molar enthalpies of the ternary system {x 1 p-xylene+x 2decane+(1–x 1x 2)diethyl carbonate} and the involved binary mixtures {p-xylene+(1–x)decane}, {xp-xylene+(1–x)diethyl carbonate} and {xdecane+(1–x)diethyl carbonate} have been determined at the temperature of 298.15 K and atmospheric pressure, over the whole composition range, using a Calvet microcalorimeter. The experimental excess molar enthalpies H m E are positive for all the binary systems studied over the whole composition range. Excess molar enthalpy for the ternary system is positive as well, showing maximum values at x 1=0, x 2=0.4920, x 3=0.5080, H m,123 E=1524 J mol–1.

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Abstract  

Excess molar enthalpies of binary mixtures for tributyl phosphate (TBP)+methanol/ethanol were measured with a TAM air Isothermal calorimeter at 298.15 K and ambient. The results for xTBP+(1–x)CH3OH are negative in the whole range of composition, while the values for xTBP+(1–x)C2H5OH change from positive values at low x to small negative values at high x. The experimental results have been correlated with the Redlich–Kister polynomial. IR spectra of the mixtures were measured to investigate the effect of hydrogen bonding in the mixture.

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Abstract  

Excess molar enthalpies, H E, for the binary mixtures {p-xylene+(1–x) octane}, {x p-xylene+(1–x) diethyl carbonate}, {x octane+(1–x) diethyl carbonate} and the corresponding ternary system {x 1 p-xylene+x 2 octane+(1–x 1x 2) diethyl carbonate} have been measured by using a Calvet microcalorimeter at 298.15 K under atmospheric pressure. The experimental H E values are all positive for the binary and ternary mixtures over the entire composition range.

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Abstract  

Forming part of the scientific project entitled ‘Study on physical properties of mixtures hydrocarbon+alcohol+ether like alternative fuels’, the present article reports experimental data of excess molar enthalpies for the ternary mixture {x 1 tert-butyl methyl ether (MTBE)+x 21-pentanol+(1−x 1x 2)octane} and the involved binary mixture {x 1-pentanol+(1−x) octane} at the temperature of 298.15 K and atmospheric pressure. No experimental excess enthalpy values were found in the currently available literature for the ternary mixture under study. The group contribution model of the UNIFAC (in the versions of Larsen, and Gmehling) were used to estimate excess enthalpy values. Several empirical expressions for estimating ternary properties from binary results were also tested.

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interesting for us to investigate the thermodynamic properties of related systems, which is important for understanding the mechanism of extraction, synergistic extraction, and the co-solvent effects in extraction process. Excess molar enthalpies at 298.15 K

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Abstract  

Excess molar enthalpies of the ternary mixture {x 1 tert-butyl methyl ether (MTBE)+x 2 ethanol+(1–x 1x 2) octane} and the involved binary mixture {x ethanol+(1–x) octane} have been measured at 298.15 K and atmospheric pressure, over the whole composition range, using a Calvet microcalorimeter. The results were fitted by means of different variable degree polynomials.

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Abstract  

Excess molar enthalpies of the ternary mixture {x 1 tert-butyl methyl ether (MTBE)+x 2 ethanol+(1–x 1x 2) hexane} and, the involved binary mixtures {x tert-butyl methyl ether (MTBE)+(1–x) ethanol}, {x tert-butyl methyl ether (MTBE)+(1–x) hexane} and {x ethanol+( 1–x) hexane} have been measured at 298.15 K and atmospheric pressure, over the whole composition range, using a Calvet microcalorimeter. The results were fitted by means of different variable degree polynomials.

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Excess molar enthalpies of dichloropropane + n-alkane mixtures

Study on the effect of increasing the chain length of the n-alkane and the influence of the chlorine position

Journal of Thermal Analysis and Calorimetry
Authors: M. Mato, J. Fernández, J. Legido, and M. Paz Andrade

Abstract  

We have determined the excess molar enthalpies
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at 298.15 K and normal atmospheric pressure for the binary mixtures containing dichloropropane and n-alkane [{xCH2ClCHClCH3 + (1−x) CnH2n+2 (n = 6, 8, 10, 12)} and {xCH2ClCH2CH2Cl + (1−x) CnH2n+2 (n = 8, 10)}] using a Calvet microcalorimeter. The
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$H_{\text{m}}^{\text{E}}$$ \end{document}
values for all the mixtures show endothermic behaviour for the whole composition range. The Redlich–Kister equation was used to correlated the experimental values. The experimental excess molar enthalpies were examined on basis of the DISQUAC group-contribution model and the UNIFAC group-contribution method using the version considered by Larsen et al. The experimental and calculated results are discussed in terms of molecular interactions and the proximity effect.
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Abstract  

Molar excess enthalpies H m E have been determined over the whole composition range for mixtures of benzene, methanol, ethanol, 1-propanol, 2-propanol and 1-butanol with quinoline at 298.15 K using a Thermometric flow calorimeter. The results reflect a strong H-bond association between an alkanol and quinoline which decreases with increasing length of the alkanol chain. The small H m E for (benzene+quinoline) reflects the similarity of the two molecules.

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