Binary Mixtures Of Ethanol Research Articles

On the study of molecular interactions of alcohol–ester binary mixtures by acoustic and viscometric studies

The values of ultrasonic velocity, density and viscosity of the binary mixtures ethanol + butyl acrylate and ethanol + butyl methacrylate have been measured over the entire composition range at 303 K. Using these data, intermolecular free length, isentropic compressibility, excess values of isentropic compressibility, viscosity and Gibb’s free energy have been determined. The excess values have been fitted to Redlich–Kister type polynomial. Analysis of the results shows the existence of specific interaction between the mixture constituents.

Solubility of 2-Butyl-3-benzofuranyl 4-(2-(Diethylamino)ethoxy)-3,5-diiodophenyl Ketone Hydrochloride (Amiodarone HCl) in Ethanol + Water and N-Methyl-2-pyrrolidone + Water Mixtures at Various Temperatures

The solubilities of amiodarone HCl (AMDH) in binary mixtures of ethanol + water and N-methyl pyrrolidone (NMP) + water at (293.2, 298.2, 303.2, 308.2, and 313.2) K are reported. In the ethanol + water system the maximum solubility of AMDH was observed at 313.2 K and an ethanol mass fraction of 0.76. The combination of the Jouyban–Acree model and van't Hoff equation was used to predict the solubility of AMDH in the mixed solvents at different temperatures. A mean relative deviation of 12.2 % was obtained for the correlated data. The standard enthalpy, entropy ,and Gibbs energy changes of solutions for AMDH in ethanol + water and NMP + water mixtures were calculated from the measured solubility data using the modified version of the van't Hoff equation.

Ebulliometric Determination and Prediction of Vapor–Liquid Equilibria for Binary Mixtures of Ethanol and Ethyl Hexanoate

The objective of this study is to measure vapor–liquid equilibria (VLE) data for an ethanol + fatty acid ethyl ester (FAEE) system. VLE data for the binary system ethanol + ethyl hexanoate were determined at pressures of (40.00 to 101.3) kPa using an ebulliometer, which could compensate for vapor hold-up. The hold-up compensable ebulliometer was designed for this study, and the experimental apparatus and procedure were verified by measuring the VLE data for ethanol + p-xylene at pressures of (40.00 to 101.3) kPa. The densities at 298.15 K for pure components investigated in this study were also measured by a densimeter. The experimental VLE data of the two binary mixtures, ethanol + p-xylene and ethanol + ethyl hexanoate, were represented by the Wilson and nonrandom two-liquid (NRTL) models. The analytical solutions of groups (ASOG) and modified universal functional activity coefficient (UNIFAC, Dortmund) group contribution models were also used to predict the VLE behavior of these binary mixtures. The VL...

Surface Tensions of Three Amyl Alcohol + Ethanol Binary Mixtures from (293.15 to 323.15) K

The surface tension of (2-methyl-2-butanol + ethanol), (3-methyl-1-butanol + ethanol), and (2-methyl-1-butanol + ethanol) binary solutions was measured over the entire composition range and at temperatures from (293.15 to 323.15) K. The experimental data were correlated with the temperature, the maximum deviation being less than 0.4 %.

Complexation of 4′-Nitrobenzo-15-crown-5 with Zn2+, Mn2+, Cr3+ and Sn4+ Cations in Acetonitrile–Ethanol Binary Mixtures

The complexation reactions of 4′-nitrobenzo-15-crown-5 (4′NB15C5) with Zn2+, Mn2+, Cr3+ and Sn4+ cations were studied in acetonitrile–ethanol (AN–EtOH) binary solvent mixtures at different temperatures by the electrical conductometry method. The stability constants of the resulting 1:1 complexes were determined from computer fitting of the conductance versus mole ratio data. The results show that the selectivity order of 4′NB15C5 for the metal cations in the AN–EtOH (mol-%AN=76) binary solvent at 298.15 K is: Cr3+>Mn2+≈Zn2+>Sn4+, but the selectivity order changes with the composition of the mixed solvents. A nonlinear relationship was observed between the stability constants (log 10 K f) of these complexes and the composition of the AN–EtOH binary solvents. The corresponding thermodynamic parameters \((\Delta H_{\mathrm{c}}^{\mathrm{o}}, \Delta S_{\mathrm{c}}^{\mathrm{o}})\) were obtained from the temperature dependence of the stability constants using van’t Hoff plots. The results show that the values and also the sign of these parameters are influenced by the nature and composition of the mixed solvents.

Novel pattern forming states for Marangoni convection in volatile binary liquids

We describe experiments on Marangoni convection in thin evaporating liquid films. The films are binary mixtures of ethanol and water exposed to the ambient room air during all experimental runs. These experiments exhibit a variety of different, often novel, patterns, depending on the concentration (weight fraction) c of ethanol. Among these are mobile circular convective patterns, which have not been previously observed, to our knowledge. The convective patterns evolve due to the evaporation of both the solvent and the solute, and their size increases substantially with the initial concentration c. The patterns reported here differ from those found in binary mixtures of NaCl and water, where only water evaporates.

Improved Aerosolization Performance of Salbutamol Sulfate Formulated with Lactose Crystallized from Binary Mixtures of Ethanol—Acetone

It has been shown that dry powder inhaler (DPI) formulations typically achieve low fine particle fractions (poor performance). A commonly held theory is that this is due, at least in part, to low levels of detachment of drug from lactose during aerosolization as a result of strong adhesion of drug particles to the carrier surfaces. Therefore, the purpose of the present study is to overcome poor aerosolization performance of DPI formulation by modification of lactose particles. Lactose particles were crystallized by adding solution in water to different ratios of binary mixtures of ethanol-acetone. The results showed that modified lactose particles had exceptional aerosolization performance that makes them superior to commercial lactose particles. Morphology assessment showed that crystallized lactose particles were less elongated, more irregular in shape, and composed of smaller primary lactose particles compared with commercial lactose. Solid-state characterization showed that commercial lactose particles were α-lactose monohydrate, whereas crystallized lactose particles were a mixture of α-lactose monohydrate and β-lactose according to the ratio of ethanol-acetone used during crystallization process. The enhanced performance could be mainly due to rougher surface and/or higher amounts of fines compared with the lactose crystallized from pure ethanol or commercial lactose.

Characterization of water–ethanol electrosprays

Abstract The electrospray (ES) ionization method is widely used in the analysis of biological molecules. The stable cone regime spray is usually obtained by adding methanol or ethanol to the electrosprayed dipolar fluid, with the role of reducing fluid surface tension. We investigate the spray onset voltages of water–ethanol mixtures starting from distilled water to pure ethanol. Positive or negative DC is applied separately in our measurements. The experimental setup allows for the study of nozzle-counter electrode gaps of up to 50 cm. Significant variations in the spray onset are observed and analyzed. The onset voltage and the surface tension of water–ethanol binary mixtures appear to be in line with Smith’s formula. The largest variations of onset values are observed for surface tensions of 20 mN/m–40 mN/m in the mixtures. The results of the study may be instrumental to electrospray electrode design and spray control.

Thermodynamic properties of biofuels: Heat capacities of binary mixtures containing ethanol and hydrocarbons up to 20 MPa and the pure compounds using a new flow calorimeter

Heat capacities are of great significance in the design of new processes and the improvement of existing ones in R&D in production plants as well as the adaptation of new products, in this case, biofuels to their use in a variety of engines and technical devices. An automated flow calorimeter has been developed for the accurate measurement of isobaric heat capacities for pure compounds and mixtures over the range (250 to 400) K and (0 to 20) MPa. In this paper, isobaric heat capacities for heptane, ethanol and the binary mixtures of ethanol with heptane and toluene are reported.

Solubility of Anthracene and Phenanthrene in Ethanol + 2,2,4-Trimethylpentane Mixtures at Different Temperatures

Solubility of anthracene and phenanthrene in binary mixtures of ethanol + 2,2,4-trimethylpentane at (298.2, 308.2, and 318.2) K are reported. Five numerical methods were used to predict the solubility of anthracene and phenanthrene in the studied binary solvent mixtures, and the mean relative deviation (MRD) was used as an error criterion. The MRD values for studied solvents are in acceptable range.

Fundamentals of semi-crystalline poly(vinylidene fluoride) membrane formation and its prospects for biofuel (ethanol and acetone) separation via pervaporation

The separation of acetone and ethanol binary mixture derived from the fermentation broth using pervaporation membranes is very challenging, most likely due to their small molecular size differences. In addition, the characteristics of acetone as a strong solvent which can easily swell and dissolve polymer materials, further increases the difficulty of separation. Flat asymmetric PVDF membranes with strong chemical resistance and good mechanical strength fabricated via mixed solvent systems show a great potential for the aforementioned binary separation via pervaporation. A mixed solvent system (50/50 wt%), i.e. NMP/THF or NMP/Acetone, coupled with the evaporation of volatile latent solvent at elevated temperatures, i.e. 40–100 °C, has effectively suppressed macrovoids and promoted dense skin layer formation in PVDF membranes as compared to that of pure NMP system. By altering the demixing process at selected evaporation temperatures, i.e. 60–80 °C, the pore structure of membranes cast from mixed solvent systems can be further designed into the desired interconnected open pore structure rather than globular structure with weaker mechanical strengths. From the trade-off line of acetone/ethanol separation via pervaporation, it can be revealed that PVDF membranes cast from mixed solvent systems at higher evaporation temperatures, i.e. 60–100 °C, exhibit superior separation factors (up to 4) with reasonably high fluxes (1–4 kg/m 2 h) as compared to those of pure NMP system. This separation performance is comparable or higher than that of commercially available PDMS membranes.

Molecular Mixture as an Effective Single-Component System

Colloidal systems exhibit a dramatic slowdown in particle dynamics at high concentrations. The study of the concentration-induced glass transition in these systems has been greatly simplified by treating the colloidal phase as an effective single component in a viscous continuum. We seek to apply an effective single-component approach to molecular systems by investigating a material that also exhibits a dramatic slowdown as the relative concentration of two components change. Our system is a binary mixture of ethanol and citric acid, in which the size ratio of the particles is 0.7. We measure the temperature and concentration dependence of the self-diffusivity of both components using pulse-gradient NMR. We model our data with an elementary free volume model and show that the self-diffusivity of both components depends on the properties of an effective single component. The particle size of the effective single component is the number-averaged size of the two components. Our results demonstrate that mixtures can be used to study the effect of particle size on glassy dynamics and are therefore useful for understanding systems that are intermediate between molecular and colloidal.

Effect of pH, temperature and solvent mole ratio on solubility of disodium 5′-guanylate in water + ethanol system

Solubility of disodium 5′-guanylate in water + ethanol binary solvent mixtures was determined by a gravimetric method in the temperature range from 283.15 K to 323.15 K, pH range from 8 to 10 and at different water/ethanol mole ratios. The effects of pH, temperature and water/ethanol mole ratio on the solubility were investigated in detail. The modified Apelblat model and the combined nearly ideal binary solvent (CNIBS)/Redlich–Kister model were selected to correlate the experimental data. The results showed that the experimental data was satisfactorily correlated by the (CNIBS)/Redlich–Kister model, but for the modified Apelblat model, the correlation was not so satisfactory in some cases.

How reliable are extrapolations to infinite dilution of partial molar properties using Redlich–Kister fittings?

An explicit method for uncertainty estimation associated with excess partial molar properties at infinite dilution calculated using standard uncertainties of Redlich–Kister parameters, fitted to data over the whole composition range, is presented for the first time. The application of this method to sets of accurate volumetric experimental data for aqueous water + ethanol binary mixtures, experimentally determined by different authors is made and the results are compared. A refinement of this method is also presented when, in very-diluted regions, Redlich–Kister lines deviate from experimental points more than their standard uncertainties. The procedure of uncertainty calculation is based on the Guide to the Expression of Uncertainty in Measurements (GUM).

Measurement and Correlation of the Densities and Viscosities of 2-Bromopropane + Ethanol Binary Mixtures at Temperatures from (298.15 to 318.15) K

ADVERTISEMENT RETURN TO ISSUEPREVAddition/CorrectionORIGINAL ARTICLEThis notice is a correctionMeasurement and Correlation of the Densities and Viscosities of 2-Bromopropane + Ethanol Binary Mixtures at Temperatures from (298.15 to 318.15) KHua Li, Xiaoshuang Chen, and Zhen ZhangCite this: J. Chem. Eng. Data 2010, 55, 12, 5960–5961Publication Date (Web):November 9, 2010Publication History Received22 October 2010Published online9 November 2010Published inissue 9 December 2010https://doi.org/10.1021/je1009834Copyright © 2010 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views278Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (273 KB) Get e-AlertsSUBJECTS:Binary mixtures,Ethanol,Order,Viscosity Get e-Alerts

Solubility of Benzoic Acid in Pure Solvents and Binary Mixtures

The solubility of benzoic acid has been determined in ethanol, toluene, heptane, cyclohexane, pentane, and chloroform and in binary mixtures of ethanol + heptane and ethanol + toluene, in the temperature range of (278.15 to 323.15) K. The solubility is high in ethanol, reasonably high in chloroform, lower in toluene, and quite low in the remaining three pure solvents. In the binary mixtures the solubility of benzoic acid increases with increasing concentration of ethanol. The solubility of benzoic acid increases with increasing temperature.

Raman and IR spectroscopy research on hydrogen bonding in water–ethanol systems

Vibrational spectroscopy provides invaluable information about hydrogen bonding in aqueous solutions. To study changes in H-bonding due to increase of ethanol concentration in water, we perform research on water–ethanol binary mixtures with various mixing ratios using a combination of Raman scattering and IR absorption techniques. We study Raman spectra from 200 to 4000 cm−1 excited at 488 nm and IR spectra from 500 and 4000 cm−1 for solutions with different ethanol concentrations from pure water to pure ethanol. Using the intensity ratio of OH stretching band taken at 3200 and 3420 cm−1 for Raman spectra and at 3240 and 3360 cm−1 for IR spectra we evaluate the strength of H-bonding. Maximal strength of H-bonding in water–ethanol mixture corresponds to ethanol concentration 15–20% w/w. We explain it by the presence of transient ethanol hydrates similar in composition to gaseous clathrates with stoichiometric water/ethanol ratio 5:1. Further weakening of H-bonding with ethanol concentration is caused by the formation of chain aggregates from ethanol/water molecules. In addition, we apply other approaches, such as multivariate curve resolution-alternating least squares analysis, decomposition of water Raman stretching band, and comparison of water Raman stretching band in ethanol solutions to that of gas clathrates to support this hypothesis.

Solubility of Artemisinin in Different Single and Binary Solvent Mixtures Between (284.15 and 323.15) K and NRTL Interaction Parameters

The solubility of artemisnin in 12 different organic solvents, methanol, ethanol, butanol, acetone, ethyl acetate, isopropyl acetate, acetonitrile, hexane, heptane, 2-butanone (MEK), methyl tert-butyl ether (MTBE), and toluene, as well as in three binary solvent mixtures of ethyl acetate + ethanol, ethyl acetate + acetone, and ethanol + acetone, within the temperature range of (284.10 and 323.15) K, is obtained. The solubility data were fitted to the Two-Liquid-Non-Random (NRTL) activity coefficient equation to obtain the model binary interaction parameters, which were used to predict the solubility of artemisinin in ethyl acetate and acetone or ethanol binary solvent mixtures. The predicted values compared favorably with the experimental data.

Densities and volumetric properties of 1,4-dioxane with ethanol, 3-methyl-1-butanol, 3-amino-1-propanol and 2-propanol binary mixtures at various temperatures

Densities (ρ), viscosities (η), and refractive indexes (n D) have been measured over the whole composition range for the binary mixtures of 1,4-dioxane with ethanol, 3-methyl-1-butanol, 3-amino-1-propanol and 2-propanol at 298.15, 303.15 and 308.15 K along with the properties of the pure components. By using the experimental values of ρ, η, and n D, excess molar volume (V E m)‚ partial molar volume (⊽ i) and excess partial molar volumes (⊽ E i) of the binary mixtures have been calculated. The numerical values of V E m were fitted to the Redlich–Kister polynomial equation and other volumetric properties were calculated. The McAllister equation has also been used to correlate the viscosity data. The variations of these parameters with composition were discussed from the point of view of intermolecular interactions in the binary mixtures.

Formation of Zein Microphases in Ethanol−Water

Zein, a major protein of corn, is soluble in binary mixtures of ethanol and water. It has an amphiphilic character and is capable of self-assembly into nano- and microsized rods, spheres, and films upon solvent evaporation. The formation of microspheres is of particular interest for the development of delivery systems. Control over structure formation requires a better understanding of zein behavior in solution. The objective of this work was to investigate the effect of zein concentration and the effect of ethanol-water ratio on the microphase behavior of zein solutions, believed to govern the morphology of microstructures after solvent evaporation. The Flory-Huggins solution theory was applied to model boundary lines between microphases in solution. The study generated information on the zein concentration-ethanol/water ratio conditions where microspheres are formed and provided insight into the microphase behavior of zein ethanolic solutions.