Mole Fraction Of 2-propanol Research Articles

Salts Effect on Isobaric Vapor–Liquid Equilibrium for the Azeotropic Mixture 2-Propanol + Water

Vapor–liquid equilibrium (VLE) data for the systems 2-propanol + water + calcium chloride, 2-propanol + water + magnesium chloride, 2-propanol + water + calcium nitrate, and 2-propanol + water + magnesium nitrate were measured at the pressure of 101.3 kPa. Experimental data of all ternary systems passed the thermodynamic consistency test by modified McDermott–Ellis method. Then, the effects of salts on the vapor phase mole fraction of 2-propanol and the relative volatility of 2-propanol to water were analyzed. Results show that the azeotropic point of the system 2-propanol and water can be removed with addition of the salts, and the salting-out effects follow the order calcium nitrate > calcium chloride > magnesium nitrate > magnesium chloride. Furthermore, the LIQUAC model was adopted to correlate the VLE experimental data of the systems. The comparative results of the average relative deviation (Δz̅) and the corresponding standard deviations (σ) between the experimental and calculated values indicate that LIQUAC model is suitable for the VLE calculation for the systems of 2-propanol + water + salts.

Vapor–Liquid Equilibria for 2-Propanol Dehydration through Extractive Distillation Using Mixed Solvent of Ethylene Glycol and Choline Chloride

The mixed solvent of ethylene glycol (EG) and choline chloride (ChCl) was tested as an entrainer for 2-propanol dehydration by extractive distillation. Isobaric vapor–liquid equilibrium (VLE) data were measured at 101.3 kPa for the quaternary system water + 2-propanol + EG + ChCl. The NRTL equation was used for the modeling of the quaternary VLE. Mean absolute deviations were 0.26 K and 0.0036 for equilibrium temperature and vapor mole fraction of 2-propanol, respectively. As compared with EG alone, the existence of ChCl in the solvent significantly decreases the activity coefficient of water and increases the activity coefficient of 2-propanol, both enhancing the relative volatility of 2-propanol to water. The azeotrope of water +2-propanol can be removed with the addition of the deep eutectic mixture EG + ChCl 2:1 at a solvent mass fraction of 0.157. The mixed solvent may be readily applied in extractive distillation of 2-propanol and water, replacing the frequently used mixed solvent of ethylene glycol and potassium acetate.

High pressure and high temperature volumetric properties of (2-propanol + di-isopropyl ether) system

New experimental density data are reported for binary mixtures of 2-propanol + di-isopropyl ether over the composition range (6 compositions; 0.15 ≤ 2-propanol mole fraction x ≤ 0.85), between 293.15 and 393.28 K, and for 23 pressures from 0.1 MPa up to 140 MPa. Measurements were performed by means of an Anton Paar vibrating tube densitometer, calibrated with an uncertainty of 7 × 10−4 g cm−3. A Tait like equation was used to fit the experimental density data, with low standard deviations. Excess volumes have been calculated from the experimental data and fitted by the Redlich–Kister equation. Moreover, the isothermal compressibility and the isobaric thermal expansivity have been derived from the Tait-like equation.

Solubility Correlation and Thermodynamic Analysis of Sorafenib Free Base and Sorafenib Tosylate in Monosolvents and Binary Solvent Mixtures

The solubility of sorafenib free base (SFB) and sorafenib tosylate (ST) in five monosolvents and binary solvents of 2-propanol + 1,4-dioxane was measured over the temperature ranged from 283.15 to 333.15 K by using a UV spectroscopy method. The solubility of SFB and ST in different monosolvents increases with increasing temperature, while in the binary solvents, the solubility shows the maximum value at 0.50 and 0.75 2-propanol mole fraction for SFB and ST, respectively. The Apelblat model and the CNIBS/R-K model were applied to correlate the solubility data, which shows that the two selected thermodynamic models could give satisfactory results. Moreover, mixing thermodynamic properties of enthalpy, entropy, and Gibbs free energy of SFB and ST were obtained based on the nonrandom two-liquid model for further understanding of the mixing behavior.

Determination and modelling of troxerutin solubility in eleven mono-solvents and (1,4-dioxane + 2-propanol) binary solvents at temperatures from 288.15 K to 323.15 K

In this work, a UV spectroscopic method was used to determine the solubility of troxerutin in eleven mono-solvents and (1,4-dioxane+2-propanol) mixtures at different temperatures from 288.15Kto 323.15K. The solubility of troxerutin was positively correlated with temperature in all selected solvents, and it showed a maximum value when the mole fraction of 2-propanol was 0.4 in binary solvent mixtures. The modified Apelblat equation, λh equation, CNIB/R-K model, NRTL model and Jouyban-Acree model were used to correlate the solubility data of troxerutin. It turned out that all the selected thermodynamic models could fit the results well, especially for the modified Apelblat equation with all the ARD values are less than 2%. Furthermore, the thermodynamic properties of troxerutin in different pure and binary solvents were also calculated and are discussed. The results indicated that the dissolution process of troxerutin in the experimental solvents was endothermic. Through analysis of enthalpy-entropy compensation in (1,4-dioxane+2-propanol) mixtures, a non-linear ΔdHo versus ΔdHo plot was obtained, indicating that the driving mechanism changes with the proportion of 2-propanol in the dissolution process of troxerutin.

Measurement and Modeling of Vapor-Liquid Equilibrium for Ternary System Water + 2-Propanol + 1-Butyl-3 methylimidazolium Chloride

Vapor-liquid equilibrium (VLE) data for water+2-propanol+1-butyl-3-methylimidazolium chloride ([bmim]Cl) were measured. Six sets of complete T, x, y data are reported, in which the 2-propanol mole fraction on IL-free basis is fixed separately at 0.1, 0.2, 0.4, 0.6, 0.8, and approximate 0.98, while the IL mass fraction is varied from 0.1 to 0.8, in an interval of 0.1. The non-random-two-liquid (NRTL) and electrolyte non-random-two-liquid (eNRTL) equations are used to correlate the experimental data with satisfactory results. The ternary VLE behavior is also modeled with the parameters obtained by correlating two data sets, in which the mole fraction of 2-propanol on IL-free basis is approximately 0.1 and 0.98. In this way, the six sets of data are reproduced satisfactorily. With the eNRTL model, the root-mean-square deviation for temperature is 0.82 K and that for vapor-phase mole fraction is 0.0078. The influences of IL on activity coefficients and relative volatility of the volatile components are also graphically illustrated.

Vapour–liquid equilibrium measurements and modelling for the ternary system (water + 2-propanol + 1-butyl-3-methylimidazolium acetate)

Vapour–liquid equilibrium (VLE) data were measured for the ternary mixtures of water (1) + 2-propanol (2) + 1-butyl-3-methylimidazolium acetate ([bmim][OAc]) (3). Complete T, x and y data were obtained in a relatively wide range of ionic liquid (IL) mass fractions up to 0.8. The data were correlated by means of NRTL and eNRTL equations with satisfactory results. Using the eNRTL equation, the ternary VLE behaviour was also modelled through correlation of two data sets, in which the mole fraction of 2-propanol on IL-free basis is respectively at 0.1 and 0.98. In this way, the six data sets were reproduced satisfactorily, with root mean square deviations of 1.06 K for temperature and 0.0098 for vapour-phase mole fractions. Owing to the regular distribution of the experimental data, good agreement between experiment and calculation was graphically presented. Effect of the IL on the VLE behaviour of the volatile components was also illustrated.

Parameters of electrical double layer on the boundary copper electrode/water-organic solution of copper sulfate

By the method of impedance spectroscopy the properties of the phase boundary of Cu|H2O + i-C3H7OH + CuSO4 system were investigated. The impedance hodographs were obtained, in the form of circles with displaced centers. The capacity values of electrical double layer, exchange currents, and resistance of the electrolyte solution depending on the mole fraction of 2-propanol were determined. The role of organic component in the formation of the electrical double layer in the studied system is elucidated.

Measurement and correlation of the solubility of MnSO 4·H 2O in 2-propanol + water + MgSO 4·7H 2O solutions

Data on the solubility of manganese sulphate monohydrate in water, and in aqueous alcohols is essential for salting-out crystallization studies. The solubilities of the quaternary system MnSO 4·H 2O + MgSO 4·7H 2O + H 2O + (CH 3) 2CHOH were determined in the temperature range 293.2–313.2 K over the 2-propanol mole fraction range of 0.00–0.07. The solubility data were used for modelling with the modified extended electrolyte non-random two-liquid (NRTL) equation. The present extension uses ion-specific parameters instead of the electrolyte-specific NRTL binary interaction parameters. This approach has feasibility for many electrolytes and mixed aqueous solution systems in principle. The model was found to correlate the solubility data satisfactorily.

Selection of ionic liquids as entrainers for separation of water and 2-propanol

A procedure for experimental evaluation of ionic liquids (ILs) as entrainers was proposed. For selection of ILs which can be potentially used for the separation of the azeotropic mixture of water and 2-propanol by extractive distillation, vapor–liquid equilibria were measured for ternary systems of water + 2-propanol + IL at 100 kPa. A previously presented ebulliometer was modified to improve the reliability of measurement of equilibrium temperature and vapor phase composition. A packed column was adopted in the place of the Cottrell pump tube to enhance the equilibration of temperature and compositions of the arising mixture of vapor and liquid. By use of the modified ebulliometer, the experimental measurement was performed in a way of continuous synthesis, in which analysis of liquid phase composition was avoided. While the mole fraction of 2-propanol calculated on IL-free basis, x ′ 2 , was kept almost unchanged at 0.95, isobaric T, x, y data were measured at different IL mass fractions. Activity coefficients of the volatile components as well as their relative volatility were obtained from the experimental data without the need of a thermodynamic model of the liquid phase. There were seven ILs in our investigation: 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF 4]), 1-ethyl-3-methylimidazolium tetrafluoroborate ([emim][BF 4]), 1-butyl-3-methylimidazolium dicyanamide ([bmim][N(CN) 2]), 1-ethyl-3-methylimidazolium dicyanamide ([emim][N(CN) 2]), 1-butyl-3-methylimidazolium acetate ([bmim][OAc]), 1-ethyl-3-methylimidazolium acetate ([emim][OAc]), and 1-butyl-3-methylimidazolium chloride ([bmim][Cl]). Results showed that the activity coefficients are mainly decided by the anions and the interactions of the anions with water and 2-propanol are in the same order, namely [Cl] − ≈ [OAc] − > [N(CN) 2] − > [BF 4] −. The similarity in the interactions cancels in some extent the effect of the ILs. While the cation has relatively small effect on the activity coefficients, their interactions with water and 2-propanol show reversed orders, namely [emim] + > [bmim] + for interactions with water and [emim] + < [bmim] + for interactions with 2-propanol. The reversed effect on the activity coefficients results in a consistent effect on the relative volatility. Among the seven ILs studied, the analysis of activity coefficients showed that the ILs with [OAc] − or [Cl] − as the anion, and [emim] + as the cation, have the most significant ability to enhance the relative volatility of the mixture of water and 2-propanol. The experimental data were correlated by the NRTL model.

Probing Molecular Structure at Interfaces for Comparison with Bulk Solution Behavior: Water/2-Propanol Mixtures Monitored by Vibrational Sum Frequency Spectroscopy

The orientation of the isopropyl group at the liquid/vapor interface in 2-propanol/water binary mixtures was studied by vibrational sum frequency spectroscopy. The CH(3) stretch modes of the two methyl groups were used to determine the molecule's orientation by employing a novel united atom approach to model the (CH(3))(2)X moiety. For this purpose, the changes in the molecular susceptibility of the isopropyl group stretches were derived in the laboratory frame as a function of the tilt and twist angles. The results indicated that the methyl groups lay down on the surface at low alcohol mole fraction and gradually twisted with increasing mole fraction. At the azeotrope, x(iso) = 0.68, one of the methyl groups aligned approximately parallel to the surface normal, whereas the other was nearly parallel with the liquid/vapor interface. When the mole fraction of 2-propanol was higher than 0.68, the orientation of 2-propanol remained almost constant. The change in the alcohol's orientation with 2-propanol mole fraction closely tracked changes in its bulk activity coefficient. Such results lead to a picture in which the surface structure and bulk properties of the system are closely linked.

Additive Effect of 1-Propanol and 2-Propanol on Molecular Organization of H2O in the Water-Rich Region: Excess Chemical Potential, Partial Molar Enthalpy and Volume of 1-Propanol in 1-Propanol–2-Propanol–H2O at 25 °C

Abstract Excess chemical potential, μ1PE, partial molar enthalpy, H1PE and volume of 1-propanol, V1PE, were determined as a function of mole fraction of 1-propanol, x1P, in mixed solvents of aqueous 2-propanol with various initial mole fraction of 2-propanol, x2P0. The 1-propanol–1-propanol interaction functions, H1P–1PE ≡ N(∂H1PE/∂n1P), and V1P–1PE ≡ N(∂V1PE/∂n1P), were evaluated by graphical differentiation. The x1P-dependence of all these quantities indicates that 1-propanol and 2-propanol modify the molecular organization of H2O in the same and additive manner in the water-rich region. The additive effect of 1-propanol and that of 2-propanol are in the ratio of (0.07/0.08).

A Rayleigh light scattering study on mixing states of 2-propanol–water binary mixtures widely used as mobile phase in separation

Rayleigh light scatterings of 2-propanol–water binary mixtures at 546 nm have been measured by using a conventional fluorophotometer at 25°C. Mean square concentration fluctuations and Kirkwood–Buff parameters of the mixtures in a range of 2-propanol mole fraction of 0.0≤ x 2pr≤0.4 (0–75% (v/v)) have been calculated from the scattering intensities. On the basis of these parameters, it has been concluded that at x 2pr<0.05 (15% (v/v)) 2-propanol is well solvated by water molecules, and hydrates consisting of one 2-propanol molecule and 20–30 water molecules are formed in the mixtures. However, at 0.05≤ x 2pr≤0.3 (15–65% (v/v)) large clusters mainly composed of 2-propanol molecules are formed in the mixtures, and these clusters are further reduced into small 2-propanol aggregates at x 2pr≥0.4. The usage of 2-propanol as organic modifier and its effects on CE and RPLC separations are also discussed in terms of microheterogeneity in the mobile phase.

Isothermal Vapor−Liquid Equilibria for the 2-Propanol + Water System Containing Poly(ethylene glycol) at 298.15 K

Isothermal vapor−liquid equilibrium measurements were performed for the 2-propanol + water system containing poly(ethylene glycol) (PEG) at 298.15 K by a flow type apparatus. Three different PEGs whose molecular weights are 200, 1000, and 20 000 were employed, and their mass fractions in the liquid phase were up to 0.35. The volatility of water was reduced by the addition of PEG, and the azeotropic point of the 2-propanol + water system was changed to a higher mole fraction of 2-propanol. Activity coefficients of solvent were calculated by assuming the monodispersity of PEG. It was found that the activity coefficients of water were selectively decreased by the addition of PEG. These phenomena did not depend on the molecular weight of PEG.

A Dynamic Light Scattering Study of Micelle Formation in Solutions of Poly(2-ethyl-2-oxazoline-dimethylsiloxane) in Water-2-Propanol Mixtures

Solutions of poly(2-ethyl-2-oxazoline-dimethylsiloxane), PEOX-PDMS, diblock copolymers in water-2-propanol mixtures were studied by dynamic light scattering. A diblock consisting of PDMS block with M n =4.8 kg mol -1 and a PEOX/PDMS degree of polymerization ratio=3 displayed three regimes in mixtures of water and 2-propanol. Compact micelles formed in pure water and at low mole fractions of 2-propanol where the hydrophobic PDMS blocks formed the core and hydrophilic PEOX blocks formed the corona. At a critical 2-propanol mole fraction and at C p ≥1 g L -1 , anomalously large micelles were observed

Vapor-Liquid Equilibria in the System 2-Propanol-2,2,4-Trimethylpentane.

rl;: 1.37505 1.3749 (3) 1.38908 1.38898 (3) d: 0.7761 0.77690 (13) 0.68341 0.68366 (3) Normal b. p., C 82.2 82.18 (3) 99.2 99.23 (3) Refractive indices were determined with a Bausch & Lomb precision refractometer (sugar) using a sodium vapor lamp illuminator. The temperature of the prisms was maintained constant within *0.05 C. by a Precision Scientific constanttemperature circulator. Twelve mixtures of the purified liquids were prepared gravimetrically. To avoid evaporation, a short rubber tube, one end closed by a plug of glass, was connected to the mouth of a 60-ml. bottle. A hypodermic needle was introduced into the rubber tube, and the bottle was evacuated by means of a vacuum pump. The empty bottle was weighed. The first component of the mixture was injected by means of a hypodermic syringe. After the bottle had been reweighed, the second component was introduced in the same manner, and the final weight determined. Three samples of each mixture were taken and placed directly between the prisms of the precision refractometer, which were kept at 30 C. A large graph of n io against mole fraction of 2-propanol was prepared and used to determine the compositions of the equilibrium mixtures. Exptl. Lit. Exptl. Lit.