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1.
In the literature, aqueous 2-((2-aminoethyl)amino) ethanol (AEEA) is identified as a promising solvent for postcombustion CO2 capture. In this work, the kinetics of CO2 absorption in the aqueous AEEA, containing a primary and a secondary amino group, is studied over a wide temperature range of 303.15-343.15 K and the amine concentration in the range of 0.47-2.89 M using the fall-in-pressure technique in a stirred cell reaction calorimeter setup with a horizontal gas-liquid interface. The overall rate constants for (AEEA + H2O + CO2) reaction system are estimated in the pseudo–first-order reaction regime. The kinetic models based on zwitterion and the termolecular reaction mechanisms are used to predict kinetic rate constants. The experimental kinetic data are better correlated using the zwitterion mechanism (AAD 9.18%) than that of the termolecular mechanism (AAD 10.4%). The density, viscosity, and physical solubility of pure components and aqueous binary mixtures of AEEA are also measured at the similar temperature and concentration ranges of rate kinetics. Empirical models are proposed to predict pure component density and viscosity data with AAD of 0.02% and 7.17%, respectively. The Redlich-Kister model, the Grunberg-Nissan model, and the O'Connell's model are used to correlate experimental density, viscosity, and physical solubility data of the binary mixtures with AAD of 0.034%, 4.92%, and 6.5%, respectively. The reaction activation energy (Ea ∼ 32 kJ/mol) of the (AEEA + H2O + CO2) system is calculated from the Arrhenius power-law model using the zwitterion mechanism, which indicates lower energy barrier than that of the reported value for monoethanolamine (∼44 kJ/mol) in the literature.  相似文献   

2.
The excess molar volume (V E), viscosity deviations (Δη) and Gibbs excess energy of activation for viscous flow (G∗E) have been investigated from density (ρ) and viscosity (η) measurements of eight binary mixtures of 1,3-dioxolane with methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butanol, and i-amyl alcohol over the entire range of mole fractions at 303.15 K. The viscosity data have been correlated with the Grunberg and Nissan equation. Furthermore, excess isentropic compressibilities (KSE) have been calculated from ultrasonic speed measurements of these binary mixtures at 303.15 K. The deviations have been fitted by a Redlich–Kister equation and the results are discussed in terms of molecular interactions and structural effects. The excess properties are found to be either negative or positive depending on the molecular interactions and the nature of the liquid mixtures. The systems studied exhibit very strong cross association through hydrogen bonding.  相似文献   

3.
This work presents a literature survey of the available data regarding the thermal conductivity of refrigerants. About 31 pure refrigerants that contain 7127 data points are selected for the temperature range of 91.35–580.00 K, a pressure range of (0.000111-500) bar, and thermal conductivity range of (0.007–0.27) W m?1 K?1 containing liquid, vapour, and supercritical phases. Seven binary and three ternary mixtures are also collected both in liquid and vapour phases with an overall of 803 data points. Based on the similarity between the pressure-volume-temperature and Tλ (thermal conductivity) P diagrams, the thermal conductivity model based on Heyen equation of state has been developed for pure refrigerants and their mixtures. The genetic algorithm is used to determine the adjustable parameters of the model. The calculation results prove that this proposed model can reproduce and predict thermal conductivity of refrigerants with good accuracy (overall AAD = 6.85% for pure compounds, AAD = 6.14% for binary mixtures and AAD = 9.32% for ternary mixtures).  相似文献   

4.
Densities,ρ, ultrasonic speeds, u, viscosities,η, and refractive indices, n, of pure benzene, benzyl alcohol (BA), benzonitrile (BN), benzoyl chloride (BC), chlorobenzene (CB) and their thirty six binary mixtures, with benzene as common component, were measured at 303.15 K over the entire mole fraction range. From these experimental data the values of deviations in ultrasonic speed, △u, isentropic compressibility, △ks,excess acoustic impedance, ZE, deviation in viscosity, Dh, and excess Gibbs free energy of activation of viscous flow, G*E, and partial molar isentropic compressibility, Kφ,20 of BA, BN, BC and CB in benzene were computed. The variation of these derived functions with composition of the mixtures suggested the increased cohesion (molecular order) in the solution and that interaction (A-B)>(A-A) or (B-B).Moreover, theoretical prediction of ultrasonic speed, viscosity and refractive index of all the four binary mixtures was made on the basis of empirical and semi-empirical relations by using the experimental values of the pure components. Comparison of theoretical results with the experimental values was made in order to assess the suitability of these relations in reproducing the experimental values of u, η and n. Also, molecular radii of pure liquids and the average molecular radii of binary mixtures were evaluated using the corresponding refractive indices of pure liquids and binary mixtures. The average molecular radii of binary mixtures were found to be additive with respect to mole fraction of the pure component.  相似文献   

5.
Density and viscosity were determined for the binary mixtures containing the ionic liquid N-octylisoquinolinium bis{(trifluoromethyl)sulfonyl}imide ([C8iQuin][NTf2]) and 1-alcohol (1-butanol, 1-hexanol, and 2-phenylethanol) at five temperatures (298.15, 308.15, 318.15, 328.15, and 338.15) K and ambient pressure. The density and viscosity correlations for these systems were tested by an empirical second-order polynomial and by the Vogel–Fucher–Tammann equation. Excess molar volumes were described by the Redlich–Kister polynomial expansion. The density and viscosity variations with compositions were described by polynomials. Viscosity deviations were calculated and correlated by the Redlich–Kister polynomial expansions. The surface tensions of pure ionic liquid and binary mixtures of [C8iQuin][NTf2] with 1-hexanol were measured at atmospheric pressure at three temperatures (298.15, 308.15, and 318.15) K. The surface tension deviations were calculated and correlated by the Redlich–Kister polynomial expansion. The surface thermodynamic functions such as surface entropy and enthalpy were derived from the temperature dependence of the surface tension values. The critical temperature, parachor, and speed of sound for pure ionic liquid were described. A qualitative analysis on these quantities in terms of molecular interactions is reported. The obtained results indicate that ionic liquid interactions with alcohols are strong dependent on the special trend of packing effects and hydrogen bonding of this ionic liquid with hydroxylic solvents. As previously observed, an increase by a 1-alcohol carbon chain length leads to lower interactions on mixing.  相似文献   

6.
The viscosities, η, and refractive indices, n, of pure dimethylsulphoxide (DMSO), benzene, toluene, o‐xylene, m‐xylene, p‐xylene and mesitylene, and those of their 54 binary mixtures, with DMSO as common component, covering the whole composition range have been measured at 298.15, 303.15, 308.15, 313.15, and 318.15 K. From the experimental data, the deviations in viscosity, Δη and deviations in molar refraction, ΔRm have been calculated. The variation of these parameters with composition and temperature of the mixtures have been discussed in terms of molecular interaction in these mixtures. The effect of the number and position of the methyl groups in these aromatic hydrocarbons on molecular interactions in these mixtures has also been discussed. The free energies, ΔG*, enthalpies, ΔH* and entropies, ΔS* of activation of viscous flow have also been obtained by using Eyring viscosity equation. The ΔH* values were found independent of temperature. The dependence of these thermodynamic parameters on composition of the mixtures has been discussed. Further, the viscosities and refractive indices of these binary mixtures were calculated theoretically from pure component data by using various empirical and semi‐empirical relations and the results were compared with the experimental findings.  相似文献   

7.
Density, electrical conductivity and viscosity of binary liquid mixtures of γ-butyrolactone, (GBL) with 1-methyl-3-propylimidazolium bis(trifluoromethylsulfonyl)imide, [pmim][NTf2], were measured at different temperatures from (293.15 to 323.15) K and at atmospheric pressure (p = 0.1 MPa) over the whole composition range. Excess molar volumes have been calculated from the experimental densities and were fitted with Redlich–Kister’s polynomial equation. Other volumetric properties have been also calculated in order to obtain information about interactions between GBL and selected ionic liquid. All the results are compared with those obtained for binary mixtures of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [bmim][NTf2], with GBL. From the viscosity measurements, the Angell strength parameter was calculated for pure ionic liquid indicating that [pmim][NTf2] is a “fragile” liquid. Electrical conductivity results were discussed in the scope of Bahe–Varela theoretical model.  相似文献   

8.
In this work, the physical properties, dynamic viscosities, densities, and speed of sound have been measured over the whole composition range and atmospheric pressure for the binary mixtures (methylcyclopentane with acetone, butanone, and 2-pentanone) at several temperatures T = (293.15, 298.15, and 303.15) K along with the properties of the pure components. Excess molar volumes, isentropic compressibility, deviations in isentropic compressibility and viscosity deviation for the binary systems at the above-mentioned temperatures were calculated and fitted to the Redlich–Kister equation to determine the fitting parameters and the root-mean-square deviations. The UNIQUAC equation was used to correlate the experimental viscosity data. The UNIFAC-VISCO method and ASOG-VISCO method, based on contribution groups, were used to predict the dynamic viscosities of the binary mixtures. The interaction parameters of cycloalkanes with ketones (CHcy/CO) have been determined for their application in the predictive UNIFAC-VISCO method.  相似文献   

9.
Excess properties calculated from the literature values of experimental density and viscosity in N,N-dimethylformamide (DMF) + 1,4-dioxane (DO) fluid binary mixtures (from 303.15 to 318.15) K can lead us to test the different correlation equations as well as their corresponding relative functions. Inspection of the Arrhenius activation energy Ea and the enthalpy of activation of viscous flow ?H* shows very close values; here we can define partial molar activation energy Ea1 and Ea2 for DMF and DO, respectively, along with their individual contribution separately. Correlation between the two Arrhenius parameters of viscosity in all compositions shows the existence of the primary distinct behaviours separated by particular mole fractions in DMF. In addition, we add that the correlation between Arrhenius parameters reveals interesting Arrhenius temperature (TA), which is closely related to the vaporisation temperature in the liquid–vapour equilibrium; moreover, the limiting corresponding partial molar properties allow us to estimate the boiling points of the pure components.  相似文献   

10.
Recently, a new statistical mechanic-based equation of state has been proposed by Mohsen-Nia and Modarress [M. Mohsen-Nia, H. Modarress, Chem. Phys. 336 (2007) 22–26] for associating pure fluids. The new association equation of state (AEOS) was successfully applied to calculate the saturated properties of water, methanol, and ammonia. In this work, the new proposed AEOS is used to evaluate the (vapour + liquid) equilibrium (VLE) of 25 associating pure compounds and the adjusted parameters are reported. The new AEOS is also extended to mixtures containing associating and non-associating compounds. The calculated saturated properties of the pure compounds are compared with those calculated by other AEOSs. The results of VLE calculation for various binary mixtures such as: alcohol/hydrocarbon, alcohol/CO2, alcohol/aromatic-hydrocarbons, and the quaternary system (H2O/CH4/CO2/H2S) indicate the capability of the new proposed AEOS for associating pure and mixture calculations.  相似文献   

11.
Densities (ρ), speeds of sound (u) and refractive indices (nD ), of the ternary mixture (diethylcarbonate + p-chloroacetophenone + 1-hexanol) and the involved binary mixtures (diethylcarbonate + p-chloroacetophenone, diethylcarbonate + 1-hexanol, and p-chloroacetophenone + 1-hexanol) have been measured over the whole composition range at 303.15 K for the liquid region and at ambient pressure. The data obtained are used to calculate isentropic compressibilities ks , isentropic compressibility deviations Δks and refractive index deviations ΔnD , of the binary and ternary mixtures. The data of isentropic compressibility deviations and refractive index deviations of the binary systems were fitted to the Redlich–Kister equation while the best correlation method for the ternary system was found using the Cibulka equation. The experimental data of the constitute binaries and ternaries are analysed to discuss the nature and strength of intermolecular interactions in these mixtures.  相似文献   

12.
In contrast to the thoroughly studied plarity properties of pure liquids, only little is known about the polarity of mixtures of liquids, although the majority of machanistic and preparative work is not carried out in pure phases. Using a widely applicable two-parameter equation, polar behavior of binary liquid mixtues can be described quantitatively as a function of their composition. Based on this equation, satisfactory explanations are found for deviations observed for binary solvent mixtures from the linear correaltion of polarity scales, as well as for the unusual activation parameters estimated by Winstein for solvolysis of tert-butyl chloride. Applications of the equation range from a rapid test for determining water contents of solvents, the study of reaction mechanisms, to polymer chemistry.  相似文献   

13.
Viscosities of binary mixtures of pyridinium based ionic liquids (1-butyl pyridinium tetrafluoroborate, [BP][BF4], 1-butyl 3-methyl pyridinium tetrafluoroborate [3-MBP][BF4], 1-butyl 4-methyl pyridinium tetrafluoroborate, [4-MBP][BF4]), and phosphonium based ionic liquids, (tetrabutyl phosphonium alaninate, [TBP][Ala]; tetrabutyl phosphonium valinate, [TBP][Val]) with the molecular solvents, water, methanol and dichloromethane, have been measured at 298.15 K. A Brookfield ultra-rheometer was employed to measure the reported viscosities. The drop in viscosity in the close vicinity of pure ionic liquid is more prominent in polar solvents like water compared to less polar solvents. The temperature dependence of this observation was also studied for binary mixtures of [4-MBP][BF4] with water in range of 298.15–323.15 K. The Vogel-Fulcher-Tamman (VFT) equation was employed to investigate the temperature dependence of the viscosities of pure pyridinium-based ionic liquids in the temperature range from 298.15–323.15 K.  相似文献   

14.
Excess molar polarization in the binary mixture of polar solutes (acetic acid, n-tributyl phosphate) in nonpolar solvents (benzene, tetrachloromethane, p-xylene) is evaluated with the help of our proposed equation. The results have been compared with those obtained from a previously proposed equation. It is observed that our proposed equation is more accurate to interpret the liquid structure and molecular association in the binary liquid mixtures.  相似文献   

15.
At present, there is a considerable amount of work devoted to the study of the thermophysical properties of pure ionic liquids, which contrasts with the few data available for their mixtures. One of the most appealing characteristics of ionic liquids is the capability of subtly changing the chemical structure of the cation and anion in order to design appropriate solvents for specific applications. Mixtures of ionic liquids increase enormously this specificity, due to the unlimited combinations that arise from mixing two or more ionic liquids. In this context, the study of the thermophysical properties of these mixtures is revealed as a fundamental task. In this work the viscosities of the ionic liquid binary mixtures with a common ion ([C6mim] + [C2mim])[BF4], ([C6mim] + [C4mim])[BF4], [C4mim]([BF4] + [MeSO4]) and [C4mim]([PF6] + [BF4]) were determined within the temperature range (298.15–308.15) K. The temperature dependence of the viscosity for pure liquids is analyzed by means of the Vogel-Tammann-Fulcher equation and several mixing rules are applied for the mixtures.  相似文献   

16.
Excess properties calculated from literature values of experimental density and viscosity in N,N-dimethylformamide (DMF) + methanol (Met) binary mixtures (from 303.15 to 323.15 K) can lead us to test different correlation equations as well as their corresponding derivative properties. Inspection of the Arrhenius activation energy (Ea) and the enthalpy (ΔH*) of activation of viscous flow shows very close values; here, we can define partial molar activation energies Ea1 and Ea2 for N,N-DMF and Met, respectively, along with their individual contribution separately. Correlation between the two Arrhenius parameters of viscosity in all compositions shows existence of main distinct interaction behaviours delimited by particular mole fractions in N,N-DMF. In addition, we add that correlation between Arrhenius parameters reveals interesting Arrhenius temperature that is closely related to the vaporisation temperature in the liquid vapour equilibrium, and the limiting corresponding partial molar properties can permit us to estimate the boiling points of the pure components.  相似文献   

17.
This articles studied and determined the viscosities of the binary mixtures of water–methanol, water–ethanol, water–propanol, water–acetone, acetone–ethanol, methanol–ethanol, and acetone–hexane and the ternary mixtures of water–methanol–ethanol and water–ethanol–acetone at 20°C. It is shown that the mixing of water with the alcohols and acetone resulted in a positive deviation of viscosity, which reached the maximum value at the water mole fraction x 1 ~ 0.7 for water–methanol, x 1 ~ 0.72 for water–ethanol, x 1 ~ 0.74 for water–propanol, and x 1 ~ 0.83 for water–acetone binary mixture. This viscosity deviation can be mainly attributed to the formation of micelles of alcohol or acetone molecules in water because of the hydrophobic attraction between the hydrocarbon chains. The micelle surfaces are surrounded by hydration layers, leading to the positive viscosity deviation in the liquid mixtures because the water in hydration layers has a much higher viscosity than bulk water. Also, the contrary observation was found in the binary mixtures of acetone–ethanol and acetone–hexane, having a negative viscosity deviation.  相似文献   

18.
Experimental densities, electrical conductivities and dynamic viscosities of the pure 1-butyl-1-methylpyrrolydinium dicyanamide ionic liquid, [bmpyrr][DCA], and its binary liquid mixtures with γ-butyrolactone (GBL) were measured at temperatures from (273.15 to 323.15) K and at pressure of 0.1 MPa over the whole composition range. From the experimental density data the related excess molar volumes were calculated and fitted using Redlich–Kister’s polynomial equation. Obtained values are negative in the whole range of ionic liquid mole fraction and at all temperatures. Other volumetric properties, such as isobaric thermal expansion coefficients, partial molar volumes and partial molar volumes at infinite dilution were also calculated, in order to obtain information about the interactions between GBL and the selected ionic liquid. Negative values of these properties for both components indicate stronger interactions between GBL and IL compared to the pure components and better packing due to the differences in size and shape of the studied molecules. From the viscosity results, the Angell strength parameter was calculated and found to be 5.47 indicating that [bmpyrr][DCA] is a “fragile” liquid. All the results are compared with those obtained for binary mixtures of 1-butyl-1-methylpyrrolydinium bis(trifluoromethylsulfonyl)imide, [bmpyrr][NTf2], with GBL.  相似文献   

19.
The knowledge and prediction of physicochemical properties of binary liquid mixtures is of great importance for understanding intermolecular interactions. Viscosities (η) have been investigated by using density (ρ) and kinematic viscosity (ν) measurements for 1,4-dioxane + water (D–W) mixtures over the entire range of mole fractions under atmospheric pressure, at 311.15, 316.15 and 320.15 K, in order to increase the studied temperatures range available from the literature and to improve the investigations. The viscosity Arrhenius activation energy of 1,4-dioxane + water mixtures was calculated from the present experimental viscosity measurements, and those presented in a previous work at only four temperatures, and for three temperatures in the present work, over the entire range of composition in the temperatures range from 293.15 to 323.15 K. Based on the partial molar activation energy from the Arrhenius equation for viscosity, interactions between water and 1,4-dioxane molecules are discussed. Comparison between some reduced Redlich–Kister functions covering the composition domain shows the existence of two distinct behaviors.  相似文献   

20.
Excess properties calculated from the literature values of experimental density and viscosity in N,N-dimethylacetamide + formamide binary mixtures between 298.15 K and 318.15 K can lead us to test different correlation equations as well as their corresponding relative functions. Inspection of the Arrhenius activation energy Ea and the enthalpy of activation of viscous flow ΔH* shows very close values. Here, we can define partial molar activation energies Ea1 and Ea2 for N,N-dimethylacetamide and formamide, respectively, along with their individual contribution separately. Correlation between the two Arrhenius parameters of viscosity in all compositions shows the existence of two main distinct behaviours separated by the mole fraction equal to 0.3 of N,N-dimethylacetamide. In addition, the correlation between Arrhenius parameters reveals interesting Arrhenius temperature, which is closely related to the vaporisation temperature in the liquid vapour equilibrium and the limiting corresponding partial molar properties can permit us to predict the boiling points of the pure components.  相似文献   

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