Artigos
URI permanente para esta coleçãohttps://repositorio.fei.edu.br/handle/FEI/800
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Resultados da Pesquisa
- Density and Derived Properties of Binary Mixtures Containing {2-(Dimethylamino)ethyl Methacrylate + Alcohols} at Temperatures from T = (293.15 to 313.15) K and Pressures of up to 35 MPa(2019) Muche D.N.F.; Olivieri G.V.; Torres R.B.© 2019 American Chemical Society. In this study, experimental density data (ρ) for binary liquid mixtures containing {2-(dimethylamino)ethyl methacrylate (DMAEMA) + methanol, or + ethanol, or + 1-propanol, or + 1-butanol, or + 1-pentanol} have been measured over the entire composition range at temperatures from T = (293.15 to 313.15) K and pressures of up to 35 MPa. Density measurements were obtained using an Anton Paar DMA 4500 vibrating-tube densimeter coupled to an external Anton Paar DMA HP high-pressure measuring cell. The experimental results for density have been fit to the Tait-Tammann equation and used to calculate the isothermal compressibility (κ T ), the thermal expansion coefficient (α p ), and the internal pressure (π). The excess molar volume (Vm E ) values have still been calculated and used to test the applicability of the extended real associated solution model (ERAS model) and the Prigogine-Flory-Patterson theory (PFP Theory). The thermodynamic results suggest that structural and chemical effects must outweigh physical effects.
- Thermodynamic properties of binary mixtures of n-butylammonium-based ionic liquids with ethanol at T = (293.15–313.15) K(2019) Bittencourt S.S.; Hoga H.E.; Torres R.B.; d'Angelo J.V.H.© 2018, Akadémiai Kiadó, Budapest, Hungary. In this study, density, speed of sound and viscosity of binary mixtures of ionic liquids + ethanol have been measured as a function of composition at T = (293.15–313.15) K and atmospheric pressure. The ionic liquids studied were: {n-butylammonium acetate (N4Ace), n-butylammonium propanoate (N4Pro), n-butylammonium hexanoate (N4Hex), and n-butylammonium decanoate (N4Dec)}. Excess molar volume, VmE, deviation in isentropic compressibility, Δ κ S , deviation in viscosity, Δ η, and excess Gibbs energy of activation of viscous flow, Δ G ∗ E , were obtained from experimental results and correlated with the Redlich–Kister polynomial equation. Ionic liquids were synthesized and characterized using 1 H-NMR, 13 C-NMR and FTIR spectroscopy techniques. For all systems studied, the values of VmE, Δ κ S and Δ η were negative over the entire composition range, whereas Δ G ∗ E values were positive over the entire composition range. The results obtained were discussed in terms of structural effects and intermolecular interactions between like and unlike molecules.
- Thermodynamics properties of binary mixtures of aqueous solutions of glycols at several temperatures and atmospheric pressure(2018) Hoga H.E.; Torres R.B.; Volpe P.L.O.© 2018 Elsevier LtdDensities (ρ), speeds of sound (u) and viscosities (η) for binary mixtures of {water + ethanol, or + ethylene glycol (EG), or + diethylene glycol (DEG), or + triethylene glycol (TEG), or + polyethylene glycol (PEG) 200, or + polyethylene glycol (PEG) 300, or + polyethylene glycol (PEG) 400, or + polyethylene glycol (PEG) 600, or + glycerol} have been determined as a function of composition at T = (293.15, 298.15, 303.15 and 308.15 K) and atmospheric pressure. From these results, excess molar volume (VmE), deviation in isentropic compressibility (ΔκS), deviation in viscosity (Δη), and excess Gibbs energy of activation for viscous flow (ΔG∗E) were calculated and fitted by the Myers-Scott equation, as a function of mole fraction. Values of VmE and ΔκS were negative over the entire composition range for all mixtures studied. The values of Δη were negative for the systems containing ethylene glycol and glycerol and positive for the systems containing ethanol, PEG 400 and PEG 600. For other systems, the deviation of viscosity presented an S-shape, with negative values at high water concentration. For all mixtures studied, the values of ΔG∗E were positive over the entire composition range. The results obtained were discussed in terms of structural effects and intermolecular interactions between like and unlike molecules.
- Thermodynamic and spectroscopic properties of binary mixtures of n-butylammonium butanoate ionic liquid with alcohols at T = (293.15–313.15) K(2017) Bittencourt S.S.; Hoga H.E.; Torres R.B.; d'Angelo J.V.H.© 2016 Elsevier LtdIn this work, density and speed of sound of binary mixtures of {n-butylammonium butanoate ionic liquid (N4Bu) + alcohols (methanol, ethanol, 1-propanol, 1-butanol and 1-pentanol)} have been measured as a function of composition at T = (293.15–313.15) K and atmospheric pressure. The results were used to calculate the excess molar volume, VmE, and deviation in isentropic compressibility, ΔκS, and correlated to the Redlich-Kister polynomial equation. N4Bu was synthesized by the method of acid-base neutralization reaction using n-butylamine and butanoic acid, and characterized using 1H NMR, 13C NMR and FTIR spectroscopy techniques. For all systems studied, the values of excess molar volumes and deviations in isentropic compressibility were negative over the entire composition range. The results obtained were discussed in terms of structural effects and intermolecular interactions between like and unlike molecules.
- Volumetric behaviour of binary mixtures of (trichloromethane + amines) at temperatures between T = (288.15 and 303.15) K at p = 0.1 MPa(2008) Magalhaes J.G.; Torres R.B.; Volpe P.L.O.In this work, densities of binary mixtures of {trichloromethane (TCM) + n-butylamine (n-BA), or + s-butylamine (s-BA), or + diethylamine (DEA), or + triethylamine (TEA)} have been determined under atmospheric pressure as a function of composition and temperature using a vibrating-tube densimeter. The temperatures studied were T = (288.15, 293.15, 298.15, and 303.15) K. The excess molar volumes (VmE), calculated from density data are negative for all studied systems and the negative deviations follow the sequence: TEA > DEA > s-BA > n-BA. Negative values of VmE for binary mixtures were attributed to the formation of hydrogen bonding and of a charge transfer complex between TCM and amines and to structural effects. The partial molar volumes at infinite dilution of each component (over(V, -)ioo) have been determined using three different methods. © 2008 Elsevier Ltd. All rights reserved.
- Volumetric and viscometric properties of binary mixtures of {methyl tert-butyl ether (MTBE) + alcohol} at several temperatures and p = 0.1 MPa: Experimental results and application of the ERAS model(2011) Hoga H.E.; Torres R.B.Densities and viscosities of binary mixtures of {methyl tert-butyl ether (MTBE) + methanol, or +ethanol, or +1-propanol, or +2-propanol, or +1-butanol, or +1-pentanol, or +1-hexanol} have been determined as a function of composition at several temperatures and atmospheric pressure. The temperatures studied were (293.15, 298.15, 303.15, and 308.15) K. The experimental results have been used to calculate the excess molar volume (VmE) and viscosity deviation (Δη). Both VmE and Δη values were negative over the entire range of mole fraction for all temperatures and systems studied. Moreover, the VmE values have been used to test the applicability of the Extended Real Associated Solution (ERAS) model. © 2011 Elsevier Ltd. All rights reserved.
- Volumetric properties of binary mixtures of (acetonitrile + amines) at several temperatures with application of the ERAS model(2016) Bittencourt S.S.; Torres R.B.© 2015 Elsevier Ltd. All rights reserved.Densities of binary mixtures of {acetonitrile + n-propylamine, or + n-butylamine, or + di-n-propylamine, or + di-n-butylamine, or + t-butylamine, or + triethylamine} at T = (293.15, 298.15, 303.15 and 308.15) K and atmospheric pressure are reported over the whole composition range. A vibrating-tube densimeter was used to determine the densities. The excess molar volume, VmE, was calculated from these results and correlated to the Redlich-Kister equation. The VmE values were negative for all the studied systems, except for the (acetonitrile + di-n-butylamine) binary mixtures which presented sigmoid behavior with positive values at high acetonitrile concentration. The partial molar volumes at infinite dilution of each component have been determined using three different methods. The VmE experimental results were also used to test the applicability of the Extended Real Association Solution model (ERAS model).
- Volumetric properties of chloroalkanes + amines mixtures: Theoretical analysis using theERAS-Model(2009) Torres R.B.; Hoga H.E.; Magalhaes J.G.; Volpe P.L.O.In this study, experimental data of excess molar volumes of {dichloromethane (DCM), or trichloromethane (TCM) + n-butylamine (n-BA), or +s-butylamine (s-BA), or +t-butylamine (t-BA), or +diethylamine (DEA), or +triethylamine (TEA)} mixtures as a function of composition have been used to test the applicability of the extended real associated solution model (ERAS-Model). The values of the excess molar volume were negative for (DCM + t-BA, or +DEA, or +TEA and TCM + n-BA, or +s-BA, or +DEA, or +TEA) mixtures and present sigmoid curves for (DCM + n-BA, or +s-BA) mixtures over the complete mole-fraction range. The agreement between theoretical and experimental results is discussed in terms of cross-association between the components present in the mixtures. © 2009 Springer Science+Business Media, LLC.
- Thermodynamic and spectroscopic study of binary mixtures of n-butylammonium oleate ionic liquid + alcohol at T = 288.15–308.15 K(2018) Olivieri G.V.; da Cunha C.S.; dos Santos Martins L.; Paegle P.A.M.; Nuncio S.D.; de Araujo Morandim-Giannetti A.; Torres R.B.© 2017, Akadémiai Kiadó, Budapest, Hungary.In this study, experimental data of density and speed of sound have been measured for binary liquid mixtures containing {n-butylammonium oleate (N4Ol) ionic liquid + 1-propanol, or + 1-butanol, or + 1-pentanol, or + 1-hexanol}, over the entire range of composition at temperatures from T = 288.15–308.15 K and atmospheric pressure. Excess molar volume, VmE, and deviation in isentropic compressibility, Δκ, were calculated using the experimental data and were fit to a Redlich–Kister type polynomial. In order to elucidate possible intermolecular interactions between the chemical species present in solution, FT-IR and 1H-NMR spectroscopic analyses were carried out. The results for all systems studied suggest that structural effects and dispersion-type interactions must predominate other possible effects.