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1.
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   

2.
Experimental (vapour + liquid) equilibrium results for the binary systems, (methanol + water) at the local atmospheric pressure of 95.3 kPa and at sub-atmospheric pressures of (15.19, 29.38, 42.66, 56.03, and 67.38) kPa, (water + glycerol) system at pressures (14.19, 29.38, 41.54, 54.72, 63.84, and 95.3) kPa and the (methanol + glycerol) system at pressures (32.02 and 45.3) kPa were obtained over the entire composition range using a Sweitoslwasky-type ebulliometer. The relationship of the liquid composition (x1) as a function of temperature (T) was found to be well represented by the Wilson model. Computed vapour phase mole fractions, activity coefficients and the measured values along with optimum Wilson parameters are presented.  相似文献   

3.
In this paper, isobaric (vapor + liquid) equilibrium (VLE) data for the binary system methanol + 2-butyl alcohol and the quaternary system methyl acetate + methanol + 2-butyl alcohol + 2-butyl acetate were determined at P = 101.33 kPa in a modified Rose still. The binary VLE data were found to be thermodynamic consistency by the Herrington method. The VLE data for the binary system were correlated by the Wilson and NRTL equations respectively, which were used to predict the VLE data of the quaternary system. The results showed that the Wilson and NRTL models matched well with the (vapor + liquid) phase equilibrium data. The deviations for the vapor-phase compositions and the equilibrium temperatures are reasonably small and the models are both suitable for these systems.  相似文献   

4.
We measured binary (vapor + liquid) equilibrium data for the {water + poly(ethylene glycol diacetyl ether) (PEGDAE) and methanol + PEGDAE} systems at pressures up to 400 kPa and temperatures from 333 K to 393 K. A static apparatus was used in this study. The measured data were correlated by the Peng–Robinson equation of state using the Wong–Sandler mixing rules with NRTL as the excess Gibbs free energy model.  相似文献   

5.
(Liquid + liquid equilibrium) (LLE) data for ternary system: (water + 2,3-butanediol + oleyl alcohol) has been measured at T = (300.2, 307.2, and 314.2) K. Complete phase diagrams were obtained by determining solubility and tie-line data. Tie-line compositions were correlated by Othmer–Tobias and Bachman methods. The nonrandom two liquids equation (NRTL) was used to correlate the phase equilibrium in the system using the interaction parameters determined from experimental data. It is found that NRTL could give a good correlation for the LLE data. Distribution coefficients and separation factors were evaluated for the immiscibility region.  相似文献   

6.
(Liquid + liquid) equilibria (LLE) data were presented for one ternary system of {water + octane + diisopropyl ether (DIPE)} and three quaternary systems of (water + 1-propanol + DIPE + octane, or methylbenzene, or heptane) at T = 298.15 K and p = 100 kPa. The experimental LLE data were correlated with the modified and extended UNIQUAC models. Distribution coefficients were derived from the experimental LLE data to evaluate the solubility behavior of components in organic and aqueous phases.  相似文献   

7.
(Liquid + liquid) equilibrium (LLE) data for the ternary mixtures of (methanol + aniline + n-octane) and (methanol + aniline + n-dodecane) at T = 298.15 K and ambient pressure are reported. The compositions of liquid phases at equilibrium were determined and the results were correlated with the UNIQUAC and NRTL activity coefficient models. The partition coefficients and the selectivity factor of methanol for the extraction of aniline from the (aniline + n-octane or n-dodecane) mixtures are calculated and compared. Based on these comparisons, the efficiency of methanol for the extraction of aniline from (aniline + n-dodecane) mixtures is higher than that for the extraction of aniline from (aniline + n-octane) mixtures. The phase diagrams for the ternary mixtures including both the experimental and correlated tie lines are presented. From the phase diagrams and the selectivity factors, it is concluded that methanol may be used as a suitable solvent in extraction of aniline from (aniline + n-octane or n-dodecane) mixtures.  相似文献   

8.
Mutual solubility data of the binary (methanol + limonene) mixture at the temperatures ranging from 288.15 K close to upper critical solution temperature, and ternary (liquid + liquid) equilibrium (tie-lines) of the (methanol + ethanol + limonene) mixture at the temperatures (288.15, 298.15, and 308.15) K have been obtained. The experimental results have been represented accurately in terms of the extended and modified UNIQUAC models with binary parameters, compared with the UNIQUAC model. The temperature dependence of binary and ternary (liquid + liquid) equilibrium for the binary (methanol + limonene) and ternary (methanol + ethanol + limonene) mixtures could be calculated successfully using the extended and modified UNIQUAC model.  相似文献   

9.
Densities, ρ speeds of sound, u and dynamic viscosities, η of the ternary mixtures {dimethyl carbonate (DMC) + methanol + ethanol} and (dimethyl carbonate + methanol + hexane) were gathered at T = (293.15, 298.15, 308.15, and 313.15) K. From experimental data viscosity deviations, Δη of the ternary mixtures were evaluated. These results have been correlated using the Cibulka equation. The fitting parameters and the standard deviations of the ternary viscosity deviations are given. UNIFAC-VISCO group contribution method was used to predict the dynamic viscosities of the ternary mixtures at several temperatures.  相似文献   

10.
The distillation of close boiling mixtures may be improved by adding a proper affinity solvent, and thereby creating an extractive distillation process. An example of a close boiling mixture that may be separated by extractive distillation is the mixture ethylbenzene/styrene. The ionic liquid 1-ethyl-3-methylimidazolium thiocyanate ([EMIM][SCN]) is a promising solvent to separate ethylbenzene and styrene by extractive distillation. In this study, (vapour + liquid) equilibrium data have been measured for the binary system (styrene + [EMIM][SCN]) over the pressure range of (3 to 20) kPa and binary and ternary (liquid + liquid) equilibrium data of the system (ethylbenzene + styrene + [EMIM][SCN]) at temperatures (313.2, 333.2 and 353.2) K. Due to the low solubility of ethylbenzene in [EMIM][SCN], it was not possible to measure accurately VLE data of the binary system (ethylbenzene + [EMIM][SCN]) and of the ternary system (ethylbenzene + styrene + [EMIM][SCN]) using the ebulliometer. Because previous work showed that the LLE selectivity is a good measure for the selectivity in VLE, we determined the selectivity with LLE. The selectivity of [EMIM][SCN] to styrene in LLE measurements ranges from 2.1 at high styrene raffinate purity to 2.6 at high ethylbenzene raffinate purity. The NRTL model can properly describe the experimental results. The rRMSD in temperature, pressure and mole fraction for the binary VLE data are respectively (0.1, 0.12 and 0.13)%. The rRMSD is only 0.7% in mole fraction for the LLE data.  相似文献   

11.
Results from gas–liquid chromatography are presented for (liquid + liquid) equilibrium of the system of mixed solvents of (hexane + methanol + 2,2,2-trifluoroethanol) at the temperatures T = (288.15, 298.15, 303.15) K, and under atmospheric pressure. The system presents type (II) liquid–liquid phase diagram. The NRTL and UNIQUAC equations reliably represent the measured data with an average root-mean-square deviation in phase-compositions equal to 1.2%. The binary interaction parameters for the associated (nonpolar + polar) system are estimated by means of the same equations. The temperature effect on the system miscibility is reasonably important.  相似文献   

12.
(Liquid + liquid) equilibrium (LLE) data for the ternary mixtures of {water (1) + phosphoric acid (2) + organic solvents (3)} were determined at T = 298.2 K and atmospheric pressure. The organic solvents were cyclohexane, 2-methyl-2-butanol (tert-amyl alcohol), and isobutyl acetate. All the investigated systems exhibit Type-1 behaviour of LLE. The immiscibility region was found to be larger for the (water + phosphoric acid + cyclohexane) ternary system. The experimental LLE results were correlated with the NRTL model, and the binary interaction parameters were obtained. The reliability of the experimental tie-line results was tested through the Othmer–Tobias and Bachman correlation equations. Distribution coefficients and separation factors were evaluated over the immiscibility regions and a comparison of the extracting capabilities of the solvents was made with respect to these factors. The experimental results indicate the superiority of cyclohexane as the preferred solvent for the extraction of phosphoric acid from its aqueous solutions.  相似文献   

13.
(Liquid + liquid) equilibrium (LLE) data of (water + ethanol + dimethyl glutarate) have been determined experimentally at T=(298.15,308.15 and 318.15) K. The reliability of the experimental tie-line data was ascertained by using the Othmer and Tobias correlation. The LLE data of the ternary mixture were predicted by UNIFAC method. Distribution coefficients and separation factors were evaluated for the immiscibility region.  相似文献   

14.
The extraction of aromatic compound toluene from alkane, dodecane, by mixed solvents (water + methanol), (water + ethanol) and (methanol + ethanol) have been studied by (liquid + liquid) equilibrium (LLE) measurements at three temperatures (298.15, 303.15, and 313.15) K and ambient pressure. The compositions of liquid phases at equilibrium were determined by gas liquid chromatography.The experimental tie-line data for three quaternary mixtures of {(water + methanol) + toluene + dodecane}, {(water + ethanol) + toluene + dodecane}, and {(methanol + ethanol) + toluene + dodecane} are presented. The experimental quaternary LLE data have been satisfactorily correlated by using the UNIQUAC and NRTL activity coefficient models. The parameters of the models have been evaluated and presented. The tie-line data of the studied quaternary mixtures also were correlated using the Hand method. The partition coefficients and the selectivity factor of solvent are calculated and compared for the three mixed solvents.The comparisons indicate that the selectivity factor for mixed solvent (methanol + ethanol) is higher than the other two mixed solvents at the three studied temperatures. However, considering the temperature variations of partition coefficients of toluene in two liquid phases at equilibrium, an optimum temperature may be obtained for an efficient extraction of toluene from dodecane by the mixed solvents.  相似文献   

15.
Precise excess volumes of mixing measurements at T = 313.15 K are reported over the whole composition range for binary mixtures: (N,N-dimethylacetamide + water), (N,N-dimethylacetamide + methanol), (N,N-dimethylacetamide + ethanol) and for the ternary mixtures (N,N-dimethylacetamide + methanol + water) and (N,N-dimethylacetamide + ethanol + water). For all the systems, large negative deviations from ideality are observed. The binary results have been fitted using the Redlich–Kister type polynomial. The possibility of predicting the ternary results from the binary ones was examined.  相似文献   

16.
(Liquid + liquid) equilibrium (LLE) and binodal curve data were determined for the systems (water + phenol + tert-butanol) at T = 298.15 K, (water + phenol + 2-butanol) and (water + phenol + 1-butanol) at T = 298.15 K and T = 313.15 K by the combined techniques of densimetry and refractometry. Type I curve (for tert-butanol) and Type II curves (for 1- and 2-butanol) were found. The data were correlated with the NRTL model and the parameters estimated present root mean square deviations below 2% for the system with tert-butanol and lower than 0.8% for the other systems.  相似文献   

17.
In this study the phase equilibrium behaviors of the binary system (CO2 + lauric acid) and the ternary system (CO2 + methanol + lauric acid) were determined. The static synthetic method, using a variable-volume view cell, was employed to obtain the experimental data in the temperature range of (293 to 343) K and pressures up to 24 MPa. The mole fractions of carbon dioxide were varied according to the systems as follows: (0.7524 to 0.9955) for the binary system (CO2 + lauric acid); (0.4616 to 0.9895) for the ternary system (CO2 + methanol + lauric acid) with a methanol to lauric acid molar ratio of (2:1); and (0.3414 to 0.9182) for the system (CO2 + methanol + lauric acid) with a methanol to lauric acid molar ratio of (6:1). For these systems (vapor + liquid), (liquid + liquid), (vapor + liquid + liquid), and (solid + fluid) transitions were observed. The phase equilibrium data obtained for the systems were modeled using the Peng–Robinson equation of state with the classical van der Waals mixing rule with a satisfactory correlation between experimental and calculated values.  相似文献   

18.
Experimental (liquid + liquid) equilibrium (LLE) data for a ternary system containing (ethylene glycol + benzene + cyclohexane) were determined at temperatures (298.15, 308.15, and 318.15) K and at atmospheric pressure. The experimental distribution coefficients and selectivity factors are presented to evaluate the efficiency of the solvent for extraction of benzene from cyclohexane. The effect of temperature in extraction of benzene from the (benzene + cyclohexane) mixture indicated that at lower temperatures the selectivity (S) is higher, but the distribution coefficient (K) is rather lower. The LLE results for the system studied were used to obtain binary interaction parameters in the UNIQUAC and NRTL models by minimizing the root mean square deviations (RMSD) between the experimental results and calculated results. Using the interaction parameters obtained, the phase equilibria in the systems were calculated and plotted. The NRTL model fits the (liquid + liquid) equilibrium data of the mixture studied slightly better. The root mean square deviations (RMSDs) obtained comparing calculated and experimental two-phase compositions are 0.92% for the NRTL model and 0.95% for the UNIQUAC model.  相似文献   

19.
(Liquid + liquid) equilibrium (LLE) data for (water + propionic acid + 2-ethyl-1-hexanol) were determined at atmospheric pressure over the temperature range of (298.15 to 308.15) K. A type-1 LLE phase diagram was obtained for this ternary system. The LLE data were correlated fairly well with UNIQUAC model, indicating the reliability of the UNIQUAC equation for this ternary system. The average root mean square deviation between the observed and calculated mole fractions was 1.57%. Distribution coefficients and separation factors were measured to evaluate the extracting capability of the solvent.  相似文献   

20.
(Liquid + liquid) equilibrium (LLE) data for ternary systems: (heptane + benzene + N-formylmorpholine), (heptane + toluene + N-formylmorpholine), and (heptane + xylene + N-formylmorpholine) have been determined experimentally at temperatures ranging from 298.15 K to 353.15 K. Complete phase diagrams were obtained by determining solubility and tie-line data. Tie-line compositions were correlated by Othmer–Tobias and Bachman methods. The universal quasichemical activity coefficient (UNIQUAC) and the non-random two liquids equation (NRTL) were used to predict the phase equilibrium in the system using the interaction parameters determined from experimental data. It is found that UNIQUAC and NRTL used for LLE could provide a good correlation. Distribution coefficients, separation factors, and selectivity were evaluated for the immiscibility region.  相似文献   

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