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1.
Effect of surfactants [polyglycerol diisostearate ethoxylates (PGDIS-E31, PGDIS-E36 and PGDIS-E40) and Tween-80], alcohols (1,2-propandiol, ethanol, 1-propanol, 1-butanol, 2-butanol and 1-pentanol), oils [isopropyl palmitate (IPP), isooctyl palmitate (IOP), dioctyl carbonate (DOC), and dioctyl hexanediate (DOH)], temperature and sodium chloride on the microemulsion formation of the surfactant/alcohol/oil/water system has been investigated by the pseudo-ternary phase diagrams. The capacities of the four surfactants in the microemulsion formation of the surfactant/alcohol/IPP/water system at surfactant/alcohol of 2:1 are in the order of PGDIS-E31 > PGDIS-E36 > Tween-80 > PGDIS-E40, whatever alcohol (ethanol, 1-propanol, and 1-butanol) is used. PGDIS-E31 and 1-butanol exhibit best synergism in the microemulsion formation. In addition, the volume, structure and polarity of oil all influence the microemulsion formation. At the optimum weight ratio 2:1 of PGDIS-E31/1-butanol, the microemulsion region of the PGDIS-E31/1-butanol/IPP/water system is the largest among the studied systems. The microemulsion system of PGDIS-E31/1-butanol/IPP/water is not sensitive to lower temperature such as 40°C. It is also not sensitive to sodium chloride when the concentration of sodium chloride is in the range of 0 to 1.0%.  相似文献   

2.
Densities, ρ and excess molar volumes, V?E of the binary mixtures of sulfolane, +methanol, +n-propanol,?+n-butanol, and +n-pentanol were measured at temperatures 298.15, 303.15, 308.15, 313.15, and 318.15?K, respectively, covering the whole composition range except methanol at 303.15–323.15?K. The V E for the systems were found to be negative and large in magnitude. The values of V E of the sulfolane, +n-butanol and sulfolane, +n-pentanol mixtures are being positive at lower and higher mole fractions of the alkanols (x 2). The magnitudes of the V E values of the mixtures are in the order sulfolane?+?methanol?>?sulfolane?+?n-propanol?>?sulfolane?+?n-butanol?>?sulfolane?+?n-pentanol. The observed values of V E for the mixtures have been explained in terms of (i) effects due to the differences in chain length of the alcohols, (ii) dipole–dipole interactions between the polar molecules, and (iii) geometric effect due to the differences in molar volume of the component molecules. These are more noticeable in the case of lower alcohols. All these properties have been expressed satisfactorily by appropriate polynomials.  相似文献   

3.
Speeds of sound, densities, and refractive indices of the binary mixtures containing ethanol+(2-methyl-1-propanol, 2-methyl-1-butanol, 1-pentanol, or 3-methyl-1-butanol) were measured at 288.15 ≤ T/K ≤ 323.15 and atmospheric condition in the whole compositional range. The effect of temperature was analyzed by several chemical terms.  相似文献   

4.
Summary. Speeds of sound, densities, and refractive indices of the binary mixtures containing ethanol+(2-methyl-1-propanol, 2-methyl-1-butanol, 1-pentanol, or 3-methyl-1-butanol) were measured at 288.15 ≤ T/K ≤ 323.15 and atmospheric condition in the whole compositional range. The effect of temperature was analyzed by several chemical terms.  相似文献   

5.
Volume changes on mixing of binary systems formed by 1,2-dichloroethane andn-alcohols, namely, ethanol,n-propanol,n-butanol,n-pentanol andn-hexanol were measured as a function of composition at 30, 35, 40 and 45 °C. At all compositions theV E values are all positive for all systems. The molar excess volumes of mixing for equimolar mixtures increase as the length of carbon chain increases.V E becomes more positive on increasing temperature. The positive value of the excess volume has been attributed to breaking of hydrogen bonds of associated species of alcohol by dilution with 1,2-dichloroethane.  相似文献   

6.
Experimental solubilities are reported for benzilic acid dissolved in ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 2-propanol, 2-butanol, 2-methyl-1-propanol, diethyl ether and methyl tert-butyl ether at 298.15?K. Results of these measurements reveal that the observed solubilities in the nine alcohol solvents fall within a fairly narrow mole fraction range of each other. Benzilic acid is also very soluble in the two ether solvents studied.  相似文献   

7.
8.
The solvent effect on liquid-phase epoxidation of allyl chloride with an aqueous solution of hydrogen peroxide on TS-1 titanium-containing silicalite was examined. 1-Butanol, 2-butanol, 1-propanol, isopropanol, methanol, ethanol, water, acetone, methyl ethyl ketone, and 1-pentanol were tested as solvents.  相似文献   

9.
The critical micelle concentrations of cetyltrimethylammonium chloride and cetyltrimethylammonium bromide in solutions of in N-methylacetami de and in N,N-dimethyl acetamide with added methanol, ethanol, n-propanol, n-butanol and n-pentanol were determined using electrical conductivity and surface tension measurements at various temperatures. Both methods show that micelles are formed in N-methyl acetamide and N, N-dimethyl acetamide solutions in a presence of n-alcohols. Critical micelle concentrations were also determined as functions of concentration of added alcohol. The data suggest that alcohol adding leads to an enhancement of penetration of alcohol into the micelle external shell that depends on the alcohol chain length. Thermodynamic parameters for micellar systems in a presence of n-alcohols were also calculated.  相似文献   

10.
A gas chromatographic method has been developed for the identification and direct determination of alcohols and methyl tert-butyl ether (MTBE) in gasolines. The technique involves simultaneous injection of the gasoline without any sample preparation onto two fused silica capillary columns of differing polarities. The method permits simultaneous determinations of methanol, ethanol, 2-propanol, tert-butanol, 1-propanol, sec-butanol, 1-butanol, and MTBE. By using an automatic sampler in combination with electronic pressure programming and BASIC programming, the determinations were performed automatically and reproducibly with a relatively short analysis time.  相似文献   

11.
Viscosity measurements have been made at 25°C on solutions of water inn-propanol, and at 15, 25, 35, and 45°C on solutions of water inn-butanol,n-pentanol, andn-hexanol over the respective solubility ranges. For most of the systems, water decreases the viscosity of the dry alcohols, while for the lower members of the series literature data report an increase in viscosity on addition of water. These results are rationalized in terms of two kinds of interaction between water molecules and alcohols: participation of water molecules in chain formation for the lower alcohols and formation of water-centered complexes for butanol and higher alcohols.  相似文献   

12.
Phase equilibria are determined over the entire composition range, through measurements on the bubble points of the binary mixtures of ethylbenzene with methanol, ethanol, n-propanol, iso-propanol, n-butanol, iso-butanol, sec-butanol and tert-butanol. A Swietoslawski-type ebulliometer is used for the measurements. The liquid phase composition versus temperature measurements, found to be well represented by the Wilson model, are used to establish the phase equilibria.  相似文献   

13.
Following a powder dehydration process, the surface-modified anhydrates (EA, PA and BA) of nitrofurantoin were obtained in a specially designed surface-modification apparatus at 60 °C via the adsorption of ethanol, n-propanol and n-butanol, respectively. The intact (IA) nitrofurantoin was used as control. The X-ray diffraction, FT-IR and DSC results suggested that the crystalline characteristics of anhydrate were not affected by surface-modification treatment, such as the adsorption of ethanol, n-propanol or n-butanol. Powder X-ray diffraction and differential scanning calorimetric (DSC) were used to determine the crystalline characteristics of the samples that had been stored at 93% relative humidity (RH) and at 40±1°C. The hydration of surface-modified samples followed a first-order process with an induction period. The hydration rate constants obtained by the X-ray diffraction method were in the order of PA≈BA<EA<IA. The associated induction periods were in the order of BA≥PA>EA>IA. On the other hand, the order of hydration rate constants measured by DSC method was PA≈BA<EA<IA with induction periods of BA≥PA>EA>IA. The values of kinetic parameters obtained by DSC method were different from those obtained by X-ray diffraction method. The results suggested that the surface-modified anhydrates were more stable in high humidity condition than intact, and the surface-modification by n-butanol or n-propanol adsorption was more effective than that by ethanol. The dissolution test for surface-modified samples was performed following the method as stipulated in the Japanese Pharmacopoeia XIII. Briefly, 20 mg of sample powder was introduced into 900 ml of distilled water at 37±0.5 °C with stirring by a paddle at 0 or 100 rpm. The dissolution kinetics was analyzed based on Hixon–Crowell equation. In the dynamic condition (100 rpm), the dissolution profile of surface-modified sample by n-butanol was superimposable to that of intact sample. In contrast, under the static dissolution condition the intact sample showed faster dissolution than the surface-modified initially. The result indicated that wetability of the sample decreased by surface-modification using n-butanol.  相似文献   

14.
Using a laser monitoring technique, the solubility of diosgenin in ethanol, 1-propanol, 1-butanol, isobutyl alcohol, tert-butanol, 1-pentanol, and iso-octyl alcohol was measured over the temperature range from (290.15 to 330.15) K at atmospheric pressure. Its corresponding (solid + liquid) equilibrium data will provide essential support for industrial design and further theoretical studies. From the experimental results, the solubility of diosgenin in ethanol, 1-propanol, 1-butanol, isobutyl alcohol, tert-butanol, 1-pentanol, and iso-octyl alcohol was found to increase with increasing temperature and decrease with the increase of the polarity of the alcohols solvents. The Apelblat equation, the ideal model and the λh equation were used to correlate the solubility values. The results showed that the three models mentioned above agreed well with the experimental data.  相似文献   

15.
The reactions of [CH3]+ and [CD3]+ with a number of C1 to C5 alcohols were studied at approximately thermal energies (0.1 eV) using a tandem Dempster ion cyclotron resonance mass spectrometer. Branching ratios obtained under single collision conditions are reported for [CH3]+ and [CD3]+ with methanol, perdeutero methanol, ethanol, allyl alcohol, 1-propanol, 2-propanol, perdeutero-2-propanol, 1-butanol, 2-butanol, t-butanol, cyclopentanol and 1-pentanol. The results are examined in terms of the mechanism of reactions and indicate that upon progression to larger alcohols, the formation of a long-lived adduct becomes less important in determining the reaction products.  相似文献   

16.
The solubility of coenzyme Q10 in ethyl acetate, n-hexane, 1-butanol, 1-propanol, 2-propanol and ethanol in the temperature range 270.15–320.15 K, under atmospheric pressure, was measured by a gravimetric method and compared with the data predicted using the conductor like screening model for realistic solvation (COSMO-RS) method. The results show that the solubilities of coenzyme Q10 in the above solvents increase with temperature. The temperature dependences of predicted solubilities were consistent with the experimental data. The experimental data were correlated with the Apelblat equation. At the same temperature, the order of increasing solubility is ethyl acetate > n-hexane > 1-butanol > 1-propanol > 2-propanol > ethanol.  相似文献   

17.
18.
Viscosities, densities, and speed of sound have been measured over the whole composition range for (methylcyclopentane with ethanol, 1-propanol, 1-butanol, 2-propanol, 2-butanol, and 2-pentanol) at T = (293.15, 298.15, and 303.15) K and atmospheric pressure along with the properties of the pure components. Excess molar volumes, isentropic compressibility, deviations in isentropic compressibility, and viscosity deviations for the binary systems at the above-mentioned temperatures were calculated and fitted to Redlich–Kister equation to determine the fitting parameters and the root-mean square deviations. UNIQUAC equation was used to correlate the experimental data. Dynamic viscosities of the binary mixtures have been predicted using UNIFAC-VISCO and ASOG-VISCO methods.  相似文献   

19.
20.
Grafting of poly(methyl acrylate) onto wool has been carried out in an aqueous medium at 45 ± 1°C by using ceric ammonium nitrate (CAN) in the presence of triethylamine, diethylamine, n-butylamine, triethanolamine, and N,N-dimethylaniline. The percentage of grafting varied with the nature and concentrations of the amines. Reactivity of the different amines toward grafting reactions followed the order: triethylamine > diethylamine > n-butylamine > triethanolamine ≥ N,N-dimethylaniline. In the presence of N,N-dimethylaniline grafting did not occur. An attempt has been made to explain the observed reactivity of Ce4+ in various amine systems in graft copolymerization reactions.  相似文献   

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