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1.
The density, ultrasonic velocity of sound and viscosity of binary mixtures of N,N-dimethyl aniline (N,NDMA) with 1-propanol, +2-propanol, +1-butanol, +2-butanol, +1-pentanol, +2-methyl-1-propanol, +2-methyl-2-propanol were measured at 303.15 K. These experimental data have been used to calculate excess volume V E , excess ultrasonic speeds u E , excess intermolecular free length L f E , excess acoustic impedance Z E , excess isentropic compressibility κ s E , deviation in viscosity Δη and excess Gibbs free energy of activation of viscous flow (G* E ). The values of L f E and κ s E are negative over the wide range of composition for all the binary mixtures, while the values of Z E are positive. These results have been used to discuss the nature of interaction between unlike molecules in terms of hydrogen bonding, dipole-dipole interaction, proton-acceptor interaction and dispersive forces. The viscosity data have been correlated using three equations: Grunberg and Nissan, Katti & Chaudhri and Hind et al. The excess/deviations were fitted by a Redlich-Kister equation and the results were analyzed in terms of specific interactions present in these mixtures.  相似文献   

2.
Measurement of densities (ρ), ultrasonic sound speeds (u) and viscosities (η) has been carried out for binary mixtures of N,N-dimethylaniline (N,N-DMA) with acetone(AC), methylethylketone (MEK), methylpropylketone (MPK), diethylketone (DEK), methylisobutylketone (MIBK), acetophenone (AP), cyclopentanone (CP), cyclohexanone (CH) and 2-methylcyclohexanone (MeCH) and their pure liquids at (303.15 K and 308.15) K over the entire composition range. These experimental data have been used to calculate the excess molar volume (VE), deviation in ultrasonic sound velocity (Δu), deviation in isentropic compressibility (Δκs) and deviation in viscosity (Δη) were evaluated. The variation of these properties with composition of the mixtures suggests dipole–dipole interactions and charge transfer complex formation between N,N-dimethylaniline and ketones. The magnitude of the property is found to depend on the chain length of the ketones molecule. These results have been fitted to the Redlich–Kister polynomial equation. The viscosity data have been correlated using three equations; Grunberg and Nissan, Katti and Chaudhri, Hind et al. for the system studied.  相似文献   

3.
Densities and viscosities of binary mixtures of Propiophenone with o-xylene, m-xylene and p-xylene were measured over the entire composition range at T=(303.15 to 318.15) K and at 0.1Mpa atmospheric pressure. Experimental data used to calculate excess molar volume (VE), deviation of viscosity (Δη), excess Gibb’s free energy (G*E) activation of viscous flow for each binary system and the results were fitted to the Redlich-Kister polynomial equation to obtain the fitting coefficients and standard deviations. Viscosity values used to compute single adjustable interaction parameters from Grunberg and Nissan, Katti and Chaudhri, Hind et al., Tamara Kurata and Frenkel relations. Deviations in thermodynamic properties of the binary mixtures were discussed in terms of their molecular interactions between the components. Viscosity data correlated with the McAllister’s three body/four body models, Heric, Auslander, and Jouyban-Acree relations having two and three adjustable parameters for the studied binary mixtures. Viscosity relations like Kendall-Monroe, Bingham, Arrhenius, and Kendall were used to calculate and compare the standard deviation percentage, (σ %), between the experimental and calculated viscosity data. The studied systems showed specific intermolecular interactions and the percentage deviations were in good agreement with the experimental values. Obtained results are useful in various chemical and industrial processes.  相似文献   

4.
Experimental densities (ρ), ultrasonic speeds (u), and refractive indices (nD) of binary mixtures of dichloromethane (DCM) with acetone (ACT) and dimethylsulfoxide (DMSO) were measured over the whole composition range at T?=?298.15, 303.15, and 308.15?K. From the experimental data, excess molar volume (VE), deviations in isentropic compressibility (Δks), deviations in intermolecular free length (ΔLf), deviations in refractive index (ΔnD), and deviations in ultrasonic speed (Δu) were calculated. Moreover, the Benson–Kiyohara theory was applied to the binary mixtures to obtain the theoretical Δks values. The COSMO calculations depending on density functional theory were utilized to estimate the σ-profiles for the DCM, ACT, and DMSO. The interpreted σ-profile trends were found supportive with the experimental findings. Applicability of different empirical and semi-empirical relations of refractive index data were tested against the measured results, and good agreement has been obtained. The possible results of intermolecular molecular interactions among mixture components were interpreted.  相似文献   

5.
Excess molar enthalpies for the ternary system of {1,2-dichloropropane (1,2-DCP)+2-pentanol+3-pentanol} and their constituent binary mixtures {1,2-DCP+2-pentanol}, {1,2-DCP+3-pentanol}, and {2-pentanol+3-pentanol} have been measured over the whole range of composition using an isothermal micro-calorimeter with flow-mixing cell at T=298.15 K and atmospheric pressure. The experimental excess molar enthalpies of all the binaries and ternary mixture, including three pseudo-binary mixtures, are positive (endothermic effect) throughout the mole fraction range, except for the binary mixture {2-pentanol+3-pentanol} in which shows a small negative values over the entire composition range. The experimental binary H m, ij E data were fitted to Redlich-Kister equation, and the Cibulka and the Morris equations were employed to correlate the ternary H m, 123 E data. Several empirical equations for predicting ternary excess enthalpies from constituent binary mixing data have been also examined and compared. The experimental results have been qualitatively discussed in terms of molecular interactions.  相似文献   

6.
The paper reports the solid-liquid phase equilibria (SLE), excess molar volume (VE), and molar refraction deviation (ΔR) for binary systems of ethanoic acid with the C3 to C5 carboxylic acids, propanoic, butanoic, and pentanoic acid, which are the main constituents of bio-butanol fermentation broth. The SLE was determined via a synthetic method using a custom-built glass tube at atmospheric pressure, whereas the thermodynamic mixture properties, VE and ΔR were obtained from directly measured density and refractive index using a precision densitometer and refractometer, respectively. All of the SLE that were determined for binary mixtures of ethanoic acid+C3-C5 carboxylic acids showed a single eutectic point and regressed well with the NRTL activity model within 0.6 K of RMSD. The VE values for the same binaries were positive for the entire composition ranges of all the systems, whereas the ΔR values were negative for all the systems. The VE and ΔR were well regressed by polynomial equations, namely Redlich-Kister within 0.006 cm3·mol?1 of the standard deviation for VE and 0.02 cm3·mol?1 for ΔR.  相似文献   

7.
Ternary excess molar enthalpies at T=298.15 K and P=101.3 kPa for the system of {1,2-dichloropropane+2-propanol+2-butanol} and their constituent binary systems {1,2-DCP+2-propanol}, {1,2-DCP+2-butanol}, and {2-propanol+2-butanol} have been measured over the whole composition range using an isothermal micro-calorimeter with flow-mixing cell. All of the binary and ternary systems, including three pseudobinary systems, show endothermic behavior except for the binary mixture {2-propanol+2-butanol}, which shows small exothermicity. The Redlich-Kister equation was used to correlate the binary H m, ij E data, and the Morris equation to correlate the ternary H m, 123 E data. Comparisons between the Morris and Radojkovi equations for the prediction of H m,123 E have been also made. The experimental results have been qualitatively discussed in terms of self-association, isomeric effect and chain length among molecules.  相似文献   

8.
The kinematic viscosities (v) were measured for nine binary solvent mixtures of 2-methoxyethanol (ME) + 1,2-dimethoxyethane (DME) at nineteen temperatures ranging from ?10 to +80°C. The experimental data have been used to test some empirical equations of the type v = v(T), v = v(X1) and v = v(T, X1). The viscosities of all the mixtures increase from the values of pure DME to that of ME as the mole fraction of ME increases, and always yield a negative excess property (vE) at all the investigated temperatures. Furthermore, thermodynamic parameters of viscous flow have been evaluated on the basis of the Eyring theory. The excess free energy of activation of viscous flow (ΔGE) vs X2 plot suggests the presence of a stable hetero-adduct, having ME : DME = 1 : 1 stoichiometric ratio.  相似文献   

9.
Viscosities (η) and densities (?) of five binary mixtures of ethanenitrile with benzene and several substituted benzenes viz methylbenzene, 1,4-dimethylbenzene, chlorobenzene and 1,2-dichlorobenzene have been experimentally determined at 308.15 K. Viscosity deviations (Δη) from the linear blending rule have been evaluated for all the mixtures studied. These are small with a maximum negative deviation of about 6% for binary mixture with benzene and maximum positive deviation of about 3% for mixture with 1,4-dimethylbenzene. Δη Values are fitted into Redlich - Kister equation and standard deviations in Δη values, σ (Δη) have been evaluated. The correlating performance of several viscosity models such as Grunberg - Nissan, Katti and Chaudhari, Hind-McLaughlin - Ubbelohde and Sedgwick has been evaluated. Grunberg-Nissan viscosity model is suitable for viscosities of several binary systems studied. The results are discussed in terms of molecular interactions between the components of binary mixtures.  相似文献   

10.
Excess molar volumes (Vm E) of constituent binary mixtures of n-decane, n-dodecane, 1-decanol and 1-dodecanol which are the products of liquid phase oxidation of n-paraffins, have been measured experimentally as a function of composition x from density measurements at 308.15 K. The excess molar volumes of n-decane-n-dodecane system have negative deviation from the ideality while that of n-dodecane-1-decanol system have positive deviation. In the other systems, excess molar volume exhibits inversion in sign. Experimental data were successfully correlated with Redlich-Kister polynomial.  相似文献   

11.
Mn-based mixed-oxide (MnOx) catalysts were modified with Fe, Ce, and Ce + Fe, and its catalytic oxidation activity was tested by using 1,2-dichlorobenzene (o-DCB) as models of chlorinated volatile organic compounds. Addition of Ce or Ce + Fe into MnOx promoted their crystals to turn into amorphous powder, enhanced their specific surface area and changed their redox property. The catalytic activity of MnOx improved remarkably by adding Ce or Ce + Fe indicating Ce plays an important role. Both Mn-Ce and Mn-Ce-Fe catalysts exhibited good stability for catalytic oxidation of o-DCB, indicating that the introduction of promoter is an important method to improve the catalytic performance.  相似文献   

12.
凌锦龙  曹枫  徐敏虹  俞丽丽 《化工学报》2011,62(5):1191-1196
常压下测定了乙酸乙酯和1,2-丙二醇二元系在298.15~323.15 K下的密度、折射率和黏度,建立了混合液密度、黏度随组成和温度变化关系的方程。计算了过量摩尔体积VE,折射率偏差ΔnD,黏度偏差Δη和过量流动活化自由能ΔG*E。结果表明,过量摩尔体积低温时在全浓度范围内为负值,但随温度升高,在富酯区变为正值;而折射率偏差高温时在富醇区为微小正值,其他情况都是负值;黏度偏差和过量流动活化自由能显示了相同的变化关系,均为负值,且都随温度降低而偏差增大。  相似文献   

13.
Chlorinated benzene, especially 1,2-dichlorobenzene (1,2-DCB), has been widely used as one of surrogate compounds of dioxin to find the noble methods to control dioxin. However, the relationship between the catalytic activity of dioxin surrogate compound and dioxin has not been understood quite well. In this work, we used a vanadium based catalyst (V2O5/TiO2) to compare catalytic activity of chlorinated benzenes and dibenzo-p-dioxins with low-chlorine content using the lab-scale system. We investigated the catalytic conversions of low-chlorinated dioxins, [2-monochlorodibenzo-p-dioxin (2-MCDD), 2,3-dichlorodibenzo-p-dioxin (2,3-DCDD)] and polychlorinated benzenes [1,2-DCB, 1,2,3,4-tetrachlorobenzene (1,2,3,4-TeCB), pentachlorobenzene (PeCB), hexachlorobenzene (HCB)] using a V2O5/TiO2 catalyst to understand quantitative relationship between dioxin and benzene with the chlorination level. The catalytic decomposition of chlorinated aromatic compounds was following 1,2-DCB > 1,2,3,4-TeCB > 2-MCDD > PeCB ≥ 2,3-DCDD > HCB. It might be more reasonable that PeCB or HCB should be used as the dioxin surrogate compound rather than 1,2-DCB. Also, we investigated the effect of both O2 content and space velocity (SV) on the catalytic decomposition of 1,2-DCB in the presence of V2O5/TiO2 catalyst because these factors should be considered significantly in combustion facilities to control various pollutants. The decomposition of 1,2-DCB shows dependency on the SV while the effect of oxygen content on the catalytic decomposition is negligible in the range of 5–20%.  相似文献   

14.
The deviation in viscosity was coupled with respective excess molar volume data to study the molecular interaction in binary mixtures with one associated component. This approach was applied to the experimentally measured viscosity and excess molar volume data of the 2-propanol+hydrocarbons at 298.15 K and 308.15 K. It was suggested that depolymerization power of aromatic hydrocarbon toward 2-propanol as well as strength of intermolecular interactions (electron-donor-acceptor type) between monomer of 2-propanol and aromatics depend on π-electron density of the aromatic hydrocarbon. These interactions were further confirmed by FTIR spectroscopy. The viscosity of these binary mixtures was best predicted by Gruenberg-Nissan correlation among the four correlations applied.  相似文献   

15.
The work presents density (ρ) and viscosity (η) data of binary system polyethylene glycol 600 (PEG) + dimethyl sulfoxide (DMSO) over the entire concentration range at T =(298.15,303.15,308.15,313.15 and 318.15) K and atmospheric pressure.On the basis of density and viscosity values,the excess properties of PEG (1) + DMSO (2) mixtures,including excess molar volume (VEm),viscosity deviation (△η),excess free energies of activation (△G*E),and isobaric thermal expansion coefficient (αp),were calculated.At the same time,in order to conjecture the density viscosity under different conditions,the density and viscosity data were fitted with the corresponding formula.The calculated results of VEm,△η,and △G*E were fitted with the Redlich-Kister equation to derive coefficients and estimate the standard deviations (σ) between the experimental and calculated values.Moreover,the intermolecular interaction of PEG with DMSO was discussed on the basis of FTIR and UV-Vis spectral results of PEG (1) + DMSO (2) mixtures.The results indicated that there were the hydrogen bonding and interactions of hvdroxvl hydrogen atoms in PEG with oxygen atoms in DMSO.  相似文献   

16.
Treatment of the chloride metallocene [η5-1,3-(Me3C)2C5H3]2ThCl2 or [η5-1,2,4-(Me3C)3C5H2]2ThCl2 with 2 equiv of PhCH2K in diethyl ether at room temperature gives, after recrystallization from a benzene solution, the benzyl metallocenes [η5-1,3-(Me3C)2C5H3]2Th(CH2Ph)2 (1) and [η5-1,2,4-(Me3C)3C5H2]2Th(CH2Ph)2 (2), respectively, in good yields. Complexes 1 and 2 have been characterized by various spectroscopic techniques, elemental analyses, and X-ray diffraction analyses. They are active catalysts for the polymerization of rac-lactide, leading to the atactic polylactides with high molecular weights and narrow molecular weight distributions.  相似文献   

17.
The excess molar volumes and excess molar enthalpies at T=298.15 K and atmospheric pressure for the binary systems {CH3CHClCH2Cl (1)+CH3(CH2) n?1OH (2)} (n=5 to 8) have been determined over the whole range of composition from the density and heat flux measurements using a digital vibrating-tube densimeter and an isothermal calorimeter, respectively. The measured excess molar volumes of all binary mixtures showed positive symmetrical trend with values increasing with chain length of 1-alkanol. Similarly, excess enthalpy values of all binary mixtures showed skewed endothermic behavior with values increasing with chain length of 1-alkanol. The maxima of excess molar enthalpy values were observed around x1=0.65 with excess enthalpy value ranging from 1,356.8 J/mol (1-pentanol) to 1,543.4 J/mol (1-octanol). The experimental results of both H m E and V m E are fitted to a modified version of Redlich-Kister equation using the Padé approximant to correlate the composition dependence. The experimental H m E data were also fitted to three local-composition models (Wilson, NRTL, and UNIQUAC). The correlation of excess enthalpy data in these binary systems using UNIQUAC model provides the most appropriate results.  相似文献   

18.
Densities (ρ) and dynamic viscosities (η) for three binary mixtures of n-decane with 1-pentanol, 1-hexanol and 1-heptanol are presented at temperatures from 293.15 to 363.15 K and atmospheric pressure over the entire composition range. The density and viscosity are measured using a vibrating tube densimeter and a cylindrical Couette type rotating viscometer, respectively. Excess molar volumes (VE), viscosity deviations (Δη) and excess Gibbs energy of activation of viscous flow (ΔG*E) are calculated from the experimental measurements. Intermo-lecular and structural interactions are indicated by the sign and magnitude of these properties. Partial molar vol-umes and infinity dilution molar partial volumes are also calculated for each binary system. These results are correlated using Redlich–Kister type equations.  相似文献   

19.
Densities ‘ρ’, ultrasonic speeds of sound ‘u’ of binary mixtures of propiophenone (PPH) with aniline, N-Methylaniline, N,N-dimethylaniline and N,N-diethylaniline were measured over the entire composition range from 303.15 K to 318.15 K and at atmospheric pressure 0.1 MPa. Experimental data of ultrasonic sound were compared and discussed with the computed values of ‘u’ from various velocity theories like Nomoto’s relation (UNOM), impedance relation (UIMP), Van Dael and Vangeel’s ideal mix relation (UVDV), Rao’s specific velocity relation (URAO), Junjie’s theory (UJUN) and Jouyban-Acree’s (UJOE) relation for the above binary mixtures over the entire mole fraction range at the studied temperatures. The results are satisfactory and are in agreement between the theoretical and the experimental values. Further, the molecular interaction parameter (α), average percentage error and Chi-square test values were computed by using the values of experimental and theoretical ultrasonic velocities. The Δu values were correlated with Redlich-Kister polynomial equation to compute the coefficients and the standard deviations of the binary mixtures. The results were analyzed in terms of intermolecular interactions.  相似文献   

20.
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