Experimental and Predicted Solubilities of HFC134a (1,1,1,2-Tetrafluoroethane) in Polyethers

López, Enriqueta R.; Mainar, Ana M.; Garcı́a, Josefa; Urieta, José S.; Fernández, Josefa

doi:10.1021/ie030623w

Cited by 19 publications

(24 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We have confirmed that an identity results from equating the alternative eqn (11) and (18) for the ideal dielectric dispersion, mediated by eqn (19) for g id A and its analogue for g id B . Since eqn (11) is fundamental to the one-liquid approach and eqn ( 18) is proper to the two-liquid approach, we conclude that the results of both approaches can be combined without conflict.…”

Section: Interplay Of One-and Two-liquid Approachessupporting

confidence: 79%

“…Glymes find application to stabilise solvates in high-energy rechargeable lithium batteries 15,16 and as synthetic lubricants in refrigerant-lubricant environment-friendly fluid mixtures. [17][18][19][20] There are numerous reports of experimental thermophysical properties of binary liquid systems containing glymes, for example with water, 21,22 alkanes, [23][24][25][26][27][28] haloalkanes 29 or dialkyl carbonates. 30 In turn, 2,2,2-trifluoroethanol is an amphiprotic hydroxilic solvent with high relative permittivity and dipole moment.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Kirkwood correlation factors in liquid mixtures from an extended Onsager–Kirkwood–Fröhlich equation

Reis

Iglesias

2011

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

Two approaches for applying the Onsager-Kirkwood-Fröhlich equation to liquid mixtures are revisited at the light of recent developments leading to the estimation of relative permittivities and refractive indices of thermodynamically ideal liquid mixtures. From the one-liquid approach, the squared permanent dipole moment of the mixture molecular-equivalent species M is demonstrated to be a mole-fraction average of squared permanent dipole moments of the components. An expression is obtained for calculating the ideal Kirkwood correlation factor of M at any composition by using only pure-constituent properties. From the two-liquid approach (Böttcher's equation), equations are obtained to describe the dependence on composition of the Kirkwood correlation factor of both components in the ideal mixture, even in mixtures of Onsager liquids. This dependency is tentatively ascribed to London dispersion forces acting between unlike molecules. It is demonstrated that Böttcher's equation can only be applied to mixtures where the relative permittivity of each component is larger than the squared refractive index of the other component. From the interplay of one- and two-liquid approaches, the ideal Kirkwood correlation factor of M and of both constituents are inter-related. Thermodynamic expressions are given for the calculation of excess Kirkwood correlation factors. In the case where permanent dipole moments are unknown, the ratio excess/ideal, termed the relative excess Kirkwood correlation factor for components and species M can still be evaluated. These ratios are related to more conventional excess properties. Density, relative permittivity and refractive index data are reported for binary mixtures of 2,2,2-trifluoroethanol with mono-, di-, tri- or tetra-glyme over the whole composition range at 288 K and 298 K. For these systems, ideal, excess and relative excess and Kirkwood correlation factors are calculated and discussed. In particular, by regarding Kirkwood correlation factors as a measure of order/molecular organisation in liquid mixtures, it is found that the formation of ideal mixtures entails a decrease of order which, for the present binary systems, is almost cancelled out upon passage to the corresponding real mixtures. It is concluded that the present formulation permits to estimate Kirkwood correlation factors of each constituent of liquid mixtures and thereby to draw information on their molecular organisation.

show abstract

Section: Interplay Of One-and Two-liquid Approachessupporting

confidence: 79%

Section: Introductionmentioning

confidence: 99%

Kirkwood correlation factors in liquid mixtures from an extended Onsager–Kirkwood–Fröhlich equation

Reis

Iglesias

2011

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

show abstract

“…Polyalkylene glycols (PAGs) were proposed as suitable lubricants in combination with R134a. Several researchers have focused their attention on such mixtures: measurements of solubility data,2–7 of density data,8–11 and of viscosity data8, 12–14 were produced.…”

Section: Introductionmentioning

confidence: 99%

A fundamental equation of state for the (R134a + triethylene glycol dimethyl ether) mixture

Marchi

Scalabrin

Ihmels³

et al. 2007

AIChE Journal

View full text Add to dashboard Cite

in Wiley InterScience (www.interscience.wiley.com).The thermodynamic properties of the mixture of 1,1,1,2-tetrafluoroethane (R134a) and triethylene glycol dimethyl ether (TriEGDME) have been modeled with equations of state in an extended corresponding states format. A recent equation of state for pure R134a was assumed as the reference while the scale factors have been obtained in neural network form by regression of experimental data for the mixture. The modeling was focused on the liquid phase, considering the possible application of such a mixture in a refrigeration plant; since the vapor pressure of pure TriEGDME is negligible over the considered temperature range, the vapor phase of the mixture at vapor-liquid equilibrium condition is almost pure R134a. Two fundamental equations are proposed herein. The first one, developed from a limited amount of experimental data is valid for R134a mole fractions greater than 0.94. The second equation was obtained from a wider data base; it has a larger number of free parameters to regress and covers the R134a mole fractions greater than 0.59. 2007 American Institute of Chemical Engineers AIChE J, 53: [1349][1350][1351][1352][1353][1354][1355][1356][1357][1358][1359][1360][1361] 2007 Keywords: extended corresponding states, neural networks, R134a, refrigerant þ lubricant mixtures, thermodynamic properties, TriEGDME IntroductionThe environmental problems connected with the use of chlorofluorocarbon (CFC) refrigerants, in particular the depletion of the stratospheric layer of ozone, have imposed the phase-out of such substances and their replacement with less harmful fluids. Consequently, the study of alternative refrigerants and of their properties has become a fundamental task for scientific and technical research.Nowadays, the fluids mainly used in the refrigeration and air-conditioning plants are hydrofluorocarbons (HFC) that show better environmental behavior, thanks to the absence of chlorine atoms in their molecules. Among the substances of this family, 1,1,1,2-tetrafluoroethane (R134a) is widely used, because of its favorable thermodynamic performances in compression cycles and its compatibility with the existing refrigeration plants designed for CFC refrigerants.The identification of a suitable alternative refrigerant does not completely solve the technical problem: in fact, in the compression plants, the working fluid is not a pure refrigerant (or a mixture of refrigerants), but a certain amount of lubricant, compatible and soluble with the refrigerant, must be added. Because the mineral oils that were used with CFCs for years show low solubility in HFC refrigerants, it is necessary to propose alternative lubricants. The problems posed by the selection of the lubricant have been widely studied in recent years; a partial review is given by Marsh and Kandil.1 Guidance for the choice of the most efficient lubricant for specific technical applications, as for instance the design of a refrigeration plant, requires the knowledge of the thermophysical properties of t...

show abstract

“…Due to the interest in these compounds, several thermophysical properties of different pure glymes and some of their mixtures with other compounds, over broad temperature and pressure ranges, were studied [10][11][12][13][14]. Following this research line in a previous study [15], the speed of sound in two glymes (triethylene glycol dimethyl ether, triglyme, or TrEGDME and tetraethylene glycol dimethyl ether, tetraglyme, or TEGDME) were reported from 293.15 to 353.15 K at pressures from atmospheric up to 100 MPa, together with density and isothermal and isentropic compressibilities.…”

Section: Introductionmentioning

confidence: 99%

Temperature and Pressure Dependences of Thermophysical Properties of Some Ethylene Glycol Dimethyl Ethers from Ultrasonic Measurements

et al. 2006

View full text Add to dashboard Cite

International audienceIn this work, the speed of sound was measured in monoglyme (monoethylene glycol dimethyl ether or MEGDME) and diglyme (diethylene glycol dimethyl ether or DEGDME) in the temperature range at pressures up to 100 MPa using a pulse echo technique operating at 3 MHz; several thermophysical properties were determined in the same P-T range from these measurements. Furthermore, the density, isothermal compressibility, and isobaric thermal expansion coefficient, determined from volumetric data (direct method) and from acoustic measurements (indirect method) for four glymes have been compared. The comparison was extended to a second-order derivative of density with pressure, namely, the nonlinear acoustic parameter B/A

show abstract

Experimental and Predicted Solubilities of HFC134a (1,1,1,2-Tetrafluoroethane) in Polyethers

Cited by 19 publications

References 35 publications

Kirkwood correlation factors in liquid mixtures from an extended Onsager–Kirkwood–Fröhlich equation

Kirkwood correlation factors in liquid mixtures from an extended Onsager–Kirkwood–Fröhlich equation

A fundamental equation of state for the (R134a + triethylene glycol dimethyl ether) mixture

Temperature and Pressure Dependences of Thermophysical Properties of Some Ethylene Glycol Dimethyl Ethers from Ultrasonic Measurements

Contact Info

Product

Resources

About