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1.
Marta M. Mato M. Illobre Pedro V. Verdes José Luis Legido María Inmaculada Paz Andrade 《Fluid Phase Equilibria》2010
Excess molar enthalpies for the ternary system {x1 2-methoxy-2-methylpropane + x2 ethanol + (1 − x1 − x2) decane} and the involved binary mixture {x ethanol + (1 − x) decane} have been measured at the temperature of 298.15 K and atmospheric pressure, over the whole composition range. No experimental excess enthalpy values were found in the currently available literature for the ternary mixture under study. The results were fitted by means of different variable-degree polynomials. Smooth representations of the results are presented and used to construct constant excess molar enthalpy contours on Roozeboom diagrams. The excess molar enthalpies for the binary and ternary system are positive over the whole range of composition. The binary mixture {x ethanol + (1 − x) decane} is asymmetric, with its maximum displace toward a high mole fraction of decane. The ternary contribution is also positive, and the representation is asymmetric. 相似文献
2.
J. M. Pico C. P. Menaut J. Fernández J. L. Legido M. I. Paz Andrade 《Journal of solution chemistry》1991,20(1):115-124
Excess molar enthalpies hE at 25 and 35° C and atmospheric pressure, are reported for the binary mixtures formed by a 2-butanone and 2-pentanone with 1-chlorobutane, 1-chloropentane, 1-chlorohexane, or 1-chlorooctane. The hE values for all the mixtures are positive, increasing as the 1-chloroalkane length increases and as the ketone length decreases. Excess molar enthalpies depend slightly on the temperature. The experimental values together with those from the literature were used to calculate the interaction parameters for the Dang-Tassios version of the UNIFAC model.Communicated at the Festsymposium celebrating Dr. Henry V. Kehiaian's 60th birthday, Clermont-Ferrand, France, 17–18 May 1990. 相似文献
3.
M. M. Mato S. M. Cebreiro P. V. Verdes J. L. Legido M. I. Paz Andrade 《Journal of Thermal Analysis and Calorimetry》2005,80(2):245-251
Summary Experimental excess molar enthalpies and densities have been measured for the ternary mixture x1MTBE+x21-propanol+(1-x1-x2)octane and the involved binary mixtures at 298.15 K and atmospheric pressure. In addition, excess molar volumes were determined from the densities of the pure liquids and mixtures. A standard Calvet microcalorimeter was employed to determine the excess molar enthalpies. Densities were measured using a DMA 4500 Anton Paar densimeter. The UNIFAC group contribution model (in the versions of Larsen et al., and Gmehling et al.) has been used to estimate excess enthalpies values. Experimental data were also used to test several empirical expressions for estimating ternary properties from experimental binary results. 相似文献
4.
Given the importance that enthalpic and entropic contributions have in the interplay between thermodynamics and self-assembly of aqueous amphiphile systems, the energetic characterisation of the system {water + 1-propoxypropan-2-ol (1-pp-2-ol)} at T = 298.15 K was made by directly measuring excess partial molar enthalpies of 1-pp-2-ol and water, over the entire composition range, at T = 298.15 K and atmospheric pressure. Derivatives of the partial molar properties with respect to the composition are used to improve the understanding of molecular interactions in the water-rich region. The present results were compared with those for the well-studied system {water + 2-butoxyethanol (nC4E1)}, the two amphiphiles being structural isomers. 相似文献
5.
J. L. Legido M. T. Lorenzana E. Jimenez J. Fernandez A. Amigo M. I. Paz Andrade 《Journal of solution chemistry》1990,19(11):1095-1102
Excess molar enthalpies h
E
and excess molar volumes v
E
of the binary liquid mixtures 2-hexanone+n-alkane (from n-heptane to n-decane) have been determined for various values of the mole fraction of hexanone at 35°C and atmospheric pressure. Excess molar enthalpies were determined by Calvet microcalorimetry and v
E
from densities measured by vibratingtube densimetry. The results are compared with the predictions of several group contribution models. 相似文献
6.
Oxygenates are used in gasoline to increase the octane number and reduce carbon monoxide emission. 2-methoxy-2,4,4-trimethylpentane (TOME) is a tertiary ether which can potentially be used in addition with current oxygenates. This compound can be produced by etherification of diisobutylene with methanol. During the etherification, water is formed due to the dehydration of methanol. The appearance of water can cause (liquid + liquid) phase split in the production process. In this work, several physical properties of systems containing water, methanol and TOME are studied for the first time. The liquid density of 2-methoxy-2,4,4-trimethylpentane is presented from T = (298.15 to 408.16) K. Excess enthalpies are reported for the binary system of (methanol + 2-methoxy-2,4,4-trimethylpentane) at (T = 298.15 K). The (liquid + liquid) equilibrium (LLE) for (water + 2-methoxy-2,4,4-trimethylpentane) from T = (283.15 to 318.15) K is determined. The LLE is also reported for the ternary system of (water + methanol + 2-methoxy-2,4,4-trimethylpentane) at T = (283.15 and 298.15) K. The UNIQUAC parameters were regressed to model VLE, excess enthalpy and LLE for the binary and ternary data with one set of parameters. 相似文献
7.
A high pressure flow-mixing isothermal calorimeter is used to determine the excess molar enthalpies of methylformate + (1-propanol, 2-propanol, 1-butanol, 2-butanol and 1-pentanol) at T = 298.15 K and p = (5.0, 10.0) MPa, and methylformate + 1-propanol at T = 333.15 K and p = 10.0 MPa. The Redlich-Kister equation is fit to the experimental results. 相似文献
8.
The excess molar volumes and excess molar enthalpies over the whole range of composition have been measured for the binary mixtures formed by 1,2-dichloropropane (1,2-DCP) with three 2-alkoxyethanol acetates at 298.15 K and atmospheric pressure using a digital vibrating-tube densimeter and an isothermal calorimeter with flow-mixing cell, respectively. The 2-alkoxyethanol acetates are ethylene glycol monomethyl ether acetate (EGMEA), ethylene glycol monoethyl ether acetate (EGEEA), and ethylene glycol monobutyl ether acetate (EGBEA). The of the mixture has been shown positive for EGMEA, ‘S-shaped’ for EGEEA, being negative at low and positive at high mole fraction of 1,2-DCP, and negative for EGBEA. All the values for the above mixtures showed an exothermic effect (negative values) which increase with increase in carbon number of the 2-alkoxyethanol acetates, showing minimum values varying from −374 J mol−1 (EGMEA) to −428 J mol−1 (EGBEA) around 0.54–0.56 mol fraction of 1,2-DCP. The experimental results of and were fitted to Redlich–Kister equation to correlate the composition dependence of both excess properties. In this work, the experimental excess enthalpy data have been also correlated using thermodynamic models (Wilson, NRTL, and UNIQUAC) and have been qualitatively discussed. 相似文献
9.
Microcalorimetric measurements of excess molar enthalpies, at 298.15 K, are reported for the two ternary systems formed by mixing either diisopropyl ether or 2-methyltetrahydrofuran with binary mixtures of cyclohexane and n-heptane. Smooth representations of the results are presented and used to construct constant excess molar enthalpy contours on Roozeboom diagrams. It is shown that useful estimates of the ternary enthalpies can be obtained from the Liebermann and Fried model, using only the physical properties of the components and their binary mixtures. 相似文献
10.
11.
Miho Kusakari Yurie OhtaHideaki Nakagawa Hiroshi KatagiriTatsuro Kijima Satoshi MurakamiShigeru Matsuba Bunpei Hatano 《Tetrahedron letters》2014
An enantioresolution of 2-methoxy-2-(1-naphtyl)propionic acid (MαNP acid) using the diastereomeric salt with chiral (R)-phenylethylamine was achieved to give enantiopure (R)-MαNP acid in 29% yield with >99% ee based on rac-MαNP acid. X-ray crystallographic analysis of diastereomeric salt revealed that (R)-MαNP acid was tightly arranged by four independent hydrogen bonds and one CH–π interaction with (R)-phenylethylamine. 相似文献
12.
Stefano Ottani Romolo FrancesconiFabio Comelli Carlo Castellari 《Thermochimica Acta》2003,401(2):87-93
Excess molar enthalpies, HmE, of binary mixtures containing poly(ethylene glycol) (PEG) 200+1,3-dioxolane, PEG 200+1,4-dioxane, PEG 200+oxolane and PEG 200+oxane were determined using a flow microcalorimeter at (288.15, 298.15 and 313.15) K and at atmospheric pressure. The HmE curves are always positive, with maxima varying from 393 J mol−1 (1,3-dioxolane) to 658 J mol−1 (oxolane), showing asymmetrical trends. The effect of the temperature is well marked on the calorimetric data that increase as the temperature is increased. The Redlich-Kister polynomial was used to estimate the binary fitting parameters. Root-mean-square deviations from the regression lines are reported. 相似文献
13.
Christopher Q. Lan 《The Journal of chemical thermodynamics》2006,38(12):1606-1611
Microcalorimetric measurements of excess enthalpies at the temperature T = 298.15 K are reported for the binary mixture, (x1C6H12 + x2C4H8O) and the two ternary mixtures {x1C6H12 + x2(C4H8O or C5H10O) + x3(C5H12O)}. Smooth representations of the results are presented and used to construct constant excess molar enthalpy contours on Roozeboom diagrams. It is shown that good estimates of the ternary enthalpies can be obtained from the Liebermann and Fried model, using only the physical properties of the components and their binary mixtures. 相似文献
14.
Densities and speeds of sound of the (2,2,4-trimethylpentane + methylbenzene + butan-1-ol) ternary system as well as all its binary sub-systems were measured at four temperatures, namely 298.15 K, 308.15 K, 318.15 K, and 328.15 K at atmospheric pressure by a vibrating-tube densimeter DSA 5000. The binary (isooctane + toluene) system was studied previously. Excess quantities (molar volume, adiabatic compressibility, and isobaric thermal expansivity) of the mixtures studied were calculated from the experimental densities and speed of sounds. The excess molar volume data were correlated using the Redlich–Kister equation. Both the positive and S-shaped excess molar volume curves were found for the systems studied. The excess molar volumes versus concentration of binary systems differed in the shape and temperature dependence. The experimental binary data were compared with literature data. The experimental excess molar volumes were analyzed by means of the Extended Real Associated Solution (ERAS) model. The experimental data and the ERAS model can help to estimate real behaviour of the systems studied. 相似文献
15.
M. M. Mato S. M. Cebreiro P. V. Verdes A. V. Pallas J. L. Legido M. I. Paz Andrade 《Journal of Thermal Analysis and Calorimetry》2005,80(2):345-349
Summary Experimental excess molar volumes for the ternary system x1MTBE+x21-propanol+(1-x1-x2) heptane and the three involved binary mixtures have been determined at 298.15 K and atmospheric pressure. Excess molar volumes were determined from the densities of the pure liquids and mixtures, using a DMA 4500 Anton Paar densimeter. The ternary mixture shows maximum values around the binary mixture MTBE+heptane and minimum values for the mixture MTBE+propanol. The ternary contribution to the excess molar volume is negative, with the exception of a range located around the rich compositions of 1-propanol. Several empirical equations predicting ternary mixture properties from experimental binary mixtures have been applied. 相似文献
16.
17.
I.M. Abdulagatov A. Tekin J. Safarov A. Shahverdiyev E. Hassel 《The Journal of chemical thermodynamics》2008,40(9):1386-1401
The density of seven {(0.0087, 0.0433, 0.1302, 0.2626, 0.4988, 0.7501, and 0.9102) mole fraction of [BMIM][BF4]} binary {methanol (1) + [BMIM][BF4] (2)} (1-butyl-3-methylimidazolium tetrafluoroborate) mixtures has been measured with a vibrating-tube densimeter. Measurements were performed at temperatures from (298 to 398) K and at pressures up to 40 MPa. The total uncertainties of density, temperature, pressure, and concentration measurements was estimated to be less than 0.15 kg · m−3, 15 mK, 5 kPa, and 10−4, respectively. The uncertainties reported in this paper are expanded uncertainties at the 95% confidence level with a coverage factor of k = 2. The effect of temperature, pressure, and concentration on the density and derived volumetric properties such as excess, apparent, and partial molar volumes was studied. The measured densities were used to develop a Tait-type equation of state for the mixture. The structural properties such as direct and total correlation function integrals and cluster size were calculated using the Krichevskii function concept and the equation of state for the mixture at infinite dilution. 相似文献
18.
In this work, solubility, volumetric and viscosity behavior were studied for the systems containing the environmentally acceptable compounds: liquid poly(ethylene glycol) (PEG200) and three ionic liquids: 1-butyl-3-methylimidazolium dicyanamide ([C4mim][dca]), trihexyltetradecyl phosphonium dicyanamide ([P6,6,6,14][dca]) and 1-hexyl-3-methylimidazolium bis{(trifluoromethyl)sulfonyl}amide ([C6mim][NTf2]). The studies were performed in a temperature range (288.15 to 328.15) K and at a pressure of 0.1 MPa. For the only system that evidenced limited miscibility, namely (PEG200 + [P6,6,6,14][dca]), the temperature-composition phase diagram at 0.1 MPa was determined, mapping the existing one- and two-phase regions. In the homogeneous region of this diagram, densities and viscosities were measured and the excess molar volumes, as well as deviations in viscosity were calculated. For the other two systems, as they are always homogeneous in the temperature ranges of the present work, these measurements and calculations were performed in the full range of compositions. The molecular interactions in the studied systems were scrutinized using the obtained excess molar volumes, deviations of viscosity, as well as Kamlet–Taft parameters of PEG200 and the ionic liquids. In addition, the excess molar Gibbs free energies of activation of viscous flow and the related enthalpies and entropies were calculated and introduced to take into consideration the differences in size of the molecules. 相似文献
19.
Measurements and analysis of excess molar volumes for the ternary mixture MTBE + 1-pentanol + decane
P. V. Verdes M. M. Mato J. Salgado J. L. Legido M. I. Paz Andrade 《Journal of Thermal Analysis and Calorimetry》2005,80(2):323-327
Summary Densities at 298.15 K and atmospheric pressure have been measured, using a DMA 4500 Anton Paar densimeter, for the ternary mixture methyl tert-butyl ether (MTBE)+1-pentanol+decane and for the involved binary mixtures MTBE+1-pentanol and 1-pentanol+decane. The excess molar volumes for the binary mixture MTBE+decane was reported in an earlier work [1]. In addition, excess molar volumes were determined from the densities of the pure liquids and mixtures. Suitable fitting equations have been used in order to correlate adequately the excess molar volumes. The empirical expressions of Kohler [18], Jacob and Fitzner [19], Colinet [20], Knobeloch and Schwartz [21], Tsao and Smith [22], Toop [23], Scatchard et al. [24], Hillert [25], Mathieson and Thynne [26] were applied to estimate ternary properties from binary results. 相似文献
20.
采用基团贡献法(GC)和分子动力学法(MD)模拟了聚间苯二甲酰间苯二胺纤维(MPDI)和聚对苯二甲酰对苯二胺(PPTA)的玻璃化转变温度, 并与实验值进行了对比. 结果表明, 使用基团贡献法和分子动力学法测得的MPDI和PPTA的玻璃化转变温度与实验值接近, 说明基团贡献法和分子动力学法可以用来预测芳香族聚酰胺的玻璃化转变温度. 在此基础上, 采用GC和MD预测了聚间苯二甲酰对苯二胺(PPIA)的玻璃化转变温度. 在MD模拟中, 对密度、 比体积、 回转半径和非键相互作用随温度的变化规律进行了分析. 结果表明, 自由体积理论能较好地解释PPIA的玻璃化转变现象, 其中非键相互作用随温度的变化是玻璃化转变的本质原因. PPIA的玻璃化转变温度介于MPDI和PPTA之间, 有望成为综合性能介于两者之间的另一种高性能聚酰胺. 相似文献