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1.
The partial molar volumes, V1(M), and the molar volume of isotactic crystalline low-molecular-weight poly(1-butene), iPBu-1, V1, have been calculated from the measured density of {iPBu-1 + solvent (n-hexane, n-heptane, n-nonane, n-decane, p-xylene, cyclohexane and chloroform)} systems. Some of the thermodynamic quantities were also obtained for the iPBu-1 with eight hydrocarbons (n-octane, n-decane, n-undecane, n-dodecane, n-tridecane, o-xylene, m-xylene, p-xylene) by the method of inverse gas chromatography at various temperatures. The weight fraction activity coefficients of the solvent at infinite dilution, omega2(infinity) and the Flory-Huggins thermodynamic interaction parameters, chi21(infinity), between polymer and solvents were determined. The partial molar free energy, deltaG2(infinity), the partial molar heat of mixing, deltaH2(infinity), at infinite dilution and the polymer solubility parameter, delta1, were calculated. Additionally, the (solid + liquid) binary mixtures equilibria, SLE, of iPBu-1 with three hydrocarbons (n-octane, n-decane and m-xylene) were studied by a dynamic method. By performing these experiments over a large concentration range, the T-x phase diagrams of the polymer-solvent systems were constructed. The excess Gibbs energy models were used to describe the nonideal behaviour of the liquid phase. The omega2(infinity) were determined from the solubility measurements and were predicted by using the UNIFAC FV model.  相似文献   

2.
A new isoquinolinium ionic liquid (IL) has been synthesised as a continuation of our work with quinolinium-based ionic liquids (ILs). The work includes specific basic characterization of synthesized compounds: N-isobutylquinolinium bromide, [BiQuin][Br] and N-isobutylquinolinium bis{(trifluoromethyl)sulfonyl}imide [BiQuin][NTf2] by NMR spectra, elementary analysis and water content. The basic thermal properties of the pure [BiQuin][NTf2], i.e. melting and glass-transition temperatures, the enthalpy of fusion as well as heat capacity at glass transition have been measured using a differential scanning microcalorimetry technique (DSC). Densities and viscosities were determined as a function of temperature. The temperature-composition phase diagrams of 8 binary mixtures composed of organic solvent dissolved in the IL: {[BiQuin][NTf2] + aromatic hydrocarbon (benzene, or toluene, or ethylbenzene, or n-propylbenzene), or an alcohol (1-butanol, or 1-hexanol, or 1-octanol, or 1-decanol)} were measured at ambient pressure. A dynamic method was used over a broad range of mole fraction and temperature from (270 to 320) K. For all the binary systems with benzene and alkylbenzenes, the eutectic diagrams were observed with an immiscibility gap in the liquid phase existing at low mole fraction of the IL with a very high upper critical solution temperature (UCST). For mixtures with alcohols, complete miscibility was observed for 1-butanol and also an immiscibility gap with UCST in the liquid phase for the remaining alcohols. The typical dependence was observed that with increasing chain length of an alcohol, the solubility decreases. The well-known NRTL equation was used to correlate experimental (solid + liquid), SLE and (liquid + liquid), LLE phase equilibrium data sets.  相似文献   

3.
Ambient pressure (solid + liquid) equilibria (SLE) and (liquid + liquid) equilibria (LLE) of binary systems--ionic liquid (IL) tetra- n-butylphosphonium p-toluenesulfonate + 1-alcohol (1-butanol, 1-hexanol, 1-octanol, 1-decanol, or 1-dodecanol), benzene, or n-alkylbenzene (toluene, ethylbenzene, n-propylbenzene)-have been determined by using dynamic method in a broad range of mole fractions and temperatures from 250 to 335 K. For binaries containing alcohol, simple eutectic diagrams were observed with complete miscibility in the liquid phase. Only in the case of system [IL + n-propylbenzene] was mutual immiscibility with an upper critical solution temperature (UCST) with low solubility of the IL in the alcohol and high solubility of the alcohol in the IL detected. The basic thermal properties of pure IL, i.e., melting and glass-transition temperatures as well as enthalpy of melting, have been measured with differential scanning microcalorimetry technique (DSC). Well-known UNIQUAC, Wilson, NRTL, NRTL1, and NRTL2 equations have been fitted to obtain experimental data sets. For the system containing immiscibility gap [IL + n-propylbenzene], parameters of the equations have been derived only from SLE data. As a measure of goodness of correlations, root-mean square deviations of temperature have been used. These experimental results were compared to the previously measured binary systems with tetra- n-butylphosphonium methanesulfonate. Changing anion from methanesulfonate to p-toluenesulfonate decreases solubilities in systems with alcohols and increases the solubilities in binary systems with benzene and alkylbenzenes.  相似文献   

4.
The solubility of benzene in 15 imidazolium, pyrrolidinium, pyridinium, and piperidinium ionic liquids has been determined; the resulting, benzene‐saturated ionic liquid solutions, also known as liquid clathrates, were examined with 1H and 19F nuclear magnetic resonance spectroscopy to try and understand the molecular interactions that control liquid clathrate formation. The results suggest that benzene interacts primarily with the cation of the ionic liquid, and that liquid clathrate formation (and benzene solubility) is controlled by the strength of the cation–anion interactions, that is, the stronger the cation–anion interaction, the lower the benzene solubility. Other factors that were determined to be important in the final amount of benzene in any given liquid clathrate phase included attractive interactions between the anion and benzene (when significant), and larger steric or free volume demands of the ions, both of which lead to greater benzene solubility.  相似文献   

5.
This work is a continuation of our wide ranging investigation on quinolinium based ionic liquids (ILs). The study includes specific basic characterisation of the synthesized compounds N-octylquinolinium bromide, [OQuin][Br] and N-octylquinolinium bis{(trifluoromethyl)sulfonyl}imide [OQuin][NTf2] by NMR spectra, elementary analysis and water content. Differential scanning calorimetry (DSC) measurements gave us properties of the pure [OQuin][NTf2] i.e. melting and glass-transition temperatures, the enthalpy of fusion as well as heat capacity at the glass transition. Densities and viscosities were determined as a function of temperature. The temperature-composition phase diagrams of 10 binary mixtures composed of organic solvent dissolved in the IL: {[OQuin][NTf2] + aromatic hydrocarbon (benzene, or thiophene, or toluene, or ethylbenzene, or n-propylbenzene), or an alcohol (1-butanol, or 1-hexanol, or 1-octanol, or 1-decanol, or 1-dodecanol)} were measured at ambient pressure. A dynamic method was used over a broad range of mole fractions and temperatures from (250 to 370) K. For mixtures with benzene and alkylbenzenes, the immiscibility gap in the liquid phase in a low mole fraction of the IL was observed with upper critical solution temperature (UCST) higher than the boiling point of the solvent. In the system with thiophene, the immiscibility gap is lower and UCST was measured. For binary mixtures with alcohols, complete miscibility in the liquid phase was observed for 1-butanol and 1-hexanol. In the systems with longer chain alcohols, the immiscibility gap with UCST was noted. Typical behaviour for ILs was observed with an increase of the chain length of an alcohol the solubility decreases. The well-known NRTL equation was used to correlate experimental (solid + liquid), SLE and (liquid + liquid), LLE phase equilibrium data sets.  相似文献   

6.
The new quinolinium ionic liquid has been synthesised as a continuation of our work with quinolinium-based ionic liquids (ILs). The work includes specific basic characterisation of synthesized compounds: N-hexylquinolinium bromide, [HQuin][Br] and N-hexylquinolinium bis{(trifluoromethyl)sulfonyl}imide [HQuin][NTf2] by NMR spectra, elementary analysis and water content. The basic thermal properties of the pure [HQuin][NTf2] i.e. melting and glass-transition temperatures, the enthalpy of fusion as well as heat capacity have been measured using a differential scanning microcalorimetry technique (DSC) and thermal analysis instrument (TA). Densities and viscosities were determined as a function of temperature. Phase equilibria for the binary systems: {[HQuin][NTf2]) + aromatic hydrocarbon (benzene, or toluene, or ethylbenzene, or n-propylbenzene), or an alcohol (1-butanol, or 1-hexanol, or 1-octanol, or 1-decanol)} have been determined at ambient pressure. A dynamic method was used over a broad range of mole fractions and temperatures from (270 to 320) K. For all the binary systems with benzene and alkylbenzenes, the eutectic diagrams were observed with immiscibility gap in the liquid phase beginning from (0.13 to 0.28) mole fraction of the IL with very high an upper critical solution temperature (UCST). For mixtures with alcohols, the complete miscibility was observed for 1-butanol and immiscibility with UCST in the liquid phase for the remaining alcohols. The typical dependence was observed, that with increasing chain length of an alcohol the solubility decreases. The well-known NRTL equation was used to correlate experimental (solid + liquid), SLE and (liquid + liquid), LLE phase equilibria data sets. For the systems containing immiscibility gaps, (IL + an alcohol) parameters of the LLE correlation were used to the prediction of SLE.  相似文献   

7.
Quinolinium ionic liquid has been prepared from 1-butylquinolinium bromide as a substrate. The work includes specific basic characterization of synthesized compound by NMR spectra, elementary analysis and water content. The basic thermal properties of the pure IL, i.e. melting and glass-transition temperatures, as well as the enthalpy of fusion have been measured using a differential scanning microcalorimetry technique (DSC). (Solid + liquid) phase equilibria (SLE) and (liquid + liquid) phase equilibria (LLE) for the binary systems: ionic liquid (IL) N-butylquinolinium bis{(trifluoromethyl)sulfonyl}imide, {([BQuin][NTf2]) + aromatic hydrocarbon (benzene, or toluene, or methylbenzene, or propylbenzene, or thiophene), or an alcohol (ethanol, or 1-butanol, or 1-hexanol, or 1-octanol, or 1-dodecanol)} have been determined at ambient pressure. A dynamic method was used over a broad range of mole fractions and temperatures from (260 to 330) K. For the binary systems, the simple eutectic diagrams were observed with immiscibility in the liquid phase with an upper critical solution temperature (UCST). For mixtures with alcohols, it was observed that with increasing chain length of an alcohol the solubility decreases and the UCST increases. In the case of mixture (IL + benzene, or alkylbenzene, or thiophene) the eutectic systems with mutual immiscibility in the liquid phase with very high UCSTs were observed. These points were not detectable with our method and they were observed at low ionic liquid mole fraction. Densities at high temperatures were determined and extrapolated to T = 298.15 K. Well-known UNIQUAC, and NRTL equations have been used to correlate experimental SLE data sets. For the systems containing immiscibility gaps {IL + an alcohol} parameters of the LLE correlation equation have been derived using only the NRTL equation.  相似文献   

8.
石油磺酸盐中活性组分的识别对于磺化原料油的选择和磺酸盐产品界面活性的稳定具有重要的指导意义.开展石油磺酸盐关键活性物质结构的确定与活性检测研究,可以提升高品质石油磺酸盐生产的可控性.采用液相色谱制备技术,结合质谱分析和界面张力测试评价,从长庆石油磺酸盐样品中成功分离制备出了具有优异界面活性的关键活性组分.试验结果表明,其活性组分占总石油磺酸盐含量的7.3%,可以将油水界面张力快速降至超低(<1.0×10^(-3) mN/m),且具有广泛的油相普适性,对于正己烷~正十六烷油相以及多种油田来源原油,均可将油水界面张力降至超低.此外,活性组分以单磺酸盐为主,平均相对分子质量为414(不含Na^(+)),相对分子质量分布范围在380~450之间,主要组成是以多种同分异构体结构形式存在的十七烷基苯磺酸盐和十八烷基苯磺酸盐混合物.  相似文献   

9.
The solubilities of solid 1-hexene and 2-methylpentane in liquid argon at a temperature of 87.3 K and in liquid nitrogen at 77.4 K have been measured by the filtration method. The hydrocarbon contents in solutions were determined using gas chromatography. The experimental value of the mole fraction solubility of solid 1-hexene in liquid argon at 87.3 K is (3.87 ± 0.74) × 10-7 and (7.94 ± 2.47) × 10-9 in liquid nitrogen at 77.4 K. The experimental value of the mole fraction solubility of solid 2-methylpentane in liquid argon at 87.3 K is (1.45 ± 0.36) × 10-5 and (6.80 ± 2.16) × 10-8 in liquid nitrogen at 77.4 K. The Preston–Prausnitz method was used for calculation of the solubilities of solid hydrocarbons in liquid argon in the temperature range 84.0–110.0 K and in liquid nitrogen from 64.0 to 90.0 K. The solvent–solute interaction parameters 112 were also calculated. At 90.0 K, liquid argon is a better solvent for solid 1-hexene and 2-methylpentane than is liquid nitrogen.  相似文献   

10.
Experimental data from dielectric investigations of solutions of flourobenzene (FB) and its mesogenic derivative (1-fluoro-4-(4-pentylcyclohexyl) benzene (FPCHB) in 1,4-dioxane are reported for various mole fractions and temperatures. The molecular dipole moments were determined using the Guggenheim-Debye method in the temperature range of 298.2 to 318.2 K. Both fluorinated compounds show a positive and small temperature coefficient for the effective dipole moment. Variations of the effective dipole moment and correlation factor, g, with mole fraction in these mixtures were investigated using the Kirkwood-Frohlich equation. Dielectric measurements were also carried out on binary mixtures of FPCHB with 1-butanol for various concentrations at 318.2 K. The Kirkwood correlation factor, the Bruggeman factor, and the excess permittivity were determined.  相似文献   

11.
(Solid + liquid) phase equilibria (SLE) and (liquid + liquid) phase equilibria (LLE) for the binary systems: ionic liquid (IL) 1-butyl-3-methylimidazolim tosylate (p-toluenesulfonate) {[BMIM][TOS] + water, an alcohol (ethanol, or 1-butanol, or 1-hexanol, or 1-octanol, or 1-decanol), or n-hexane, or an aromatic hydrocarbons (benzene, or toluene, or ethylbenzene, or propylbenzene, or thiophene)} have been determined at ambient pressure. A dynamic method was used over a broad range of mole fractions and temperatures from (230 to 340) K. For the binary systems containing water, or an alcohol, simple eutectic diagrams were observed with complete miscibility in the liquid phase. As usual, with increasing chain length of the alcohol the solubility decreases. In the case of mixtures {IL + n-hexane, or benzene, or alkylbenzene, or thiophene} the eutectic systems with mutual immiscibility in the liquid phase with an upper critical solution temperature (UCST) were detected. The basic thermal properties of the pure IL, i.e. melting and glass-transition temperatures, as well as the enthalpy of fusion have been measured using a differential scanning microcalorimetry technique (DSC). Density at high temperatures was determined and extrapolated to 298.15 K. Well-known UNIQUAC, Wilson and NRTL equations have been used to correlate experimental SLE data sets for alcohols and water. For the systems containing immiscibility gaps {IL + n-hexane, or benzene, or alkylbenzene, or thiophene}, parameters of the LLE correlation equation have been derived using only the NRTL equation.  相似文献   

12.
(Solid + liquid) phase diagrams, SLE have been determined for (octan-1-ol, or nonan-1-ol, or decan-1-ol, or undecan-1-ol + benzonitrile) and for (hexylamine, or octylamine, or decylamine, or 1,3-diaminopropane + benzonitrile) using a cryometric dynamic method at atmospheric pressure. Simple eutectic systems with complete immiscibility in the solid phase and complete miscibility on the liquid phase have been observed. The solubility decreases with an increase of the number of carbon atoms in the alkan-1-ol, or amine chain. The temperature of the eutectic points increases and shifts to lower alkan-1-ol, or amine mole fractions as the alkyl chain length of the alkan-1-ol, or amine increases. The higher intermolecular interaction was observed for the (alkan-1-ol + benzonitrile) systems.  相似文献   

13.
The solubility and dissolution thermodynamics of new c-Met inhibitor, ABN401, were determined in eleven solvents and Transcutol® HP–water mixture (TWM) from 298.15 to 318.15 K. The experimental solubilities were validated using five mathematical models, namely modified Apelblat, van’t Hoff, Buchowski–Ksiazaczak λh, Yalkowsky, and Jouyban–Acree van’t Hoff models. The experimental results were correlated and utilized further to investigate the feasibility of nanosuspension formation using liquid anti-solvent precipitation. Thermodynamic solubility of ABN401 increased significantly with the increase in temperature and maximum solubility was obtained with Transcutol® HP while low solubility in was obtained water. An activity coefficient study indicated that high molecular interaction was observed in ABN401–Transcutol® HP (THP). The solubility increased proportionately as the mole fraction of Transcutol® HP increased in TWM, which was also supported by a solvent effect study. The result suggested endothermic and entropy-driven dissolution. Based on the solubility, nanosuspension was designed with Transcutol® HP as solvent, and water as anti-solvent. The mean particle size of nanosuspension decreased to 43.05 nm when the mole fraction of ABN401 in THP, and mole fraction of ABN401 in TWM mixture were decreased to 0.04 and 0.1. The ultrasonicated nanosuspension appeared to give comparatively higher dissolution than micronized nanosuspension and provide a candidate formulation for in vivo purposes.  相似文献   

14.
Generalized formulation is presented for calculating simple eutectic type solid-liquid phase diagrams for binary and ternary systems by using the Wilson equation for molar excess Gibbs energy in the liquid phase. The liquidus surface and eutectic points of molten salt mixtures with a common ion were calculated and compared with experimental values. The average error in the estimation of ternary eutectic composition was ± 0.013 (mole fraction) for the two ternary systems tested. The agreement was generally better than that obtained with the regular solution approximation.  相似文献   

15.
New polythioesters have been obtained in the interfacial polycondensation of 4,4′-di(mercaptomethyl)benzophenone with terephthaloyl, isophthaloyl and phthaloyl chlorides. The reactions were carried out at room temperature with the use of 10% excess of acid chloride per mole of mercaptan with vigorous stirring (2000 rpm). The organic phase was composed of benzene and hexane in equal volumes and the ratio of this mixture to water also was 1:1. The structure of the polythioesters was determined from elementary analysis and the infrared spectra. The molecular weight was not determined because of the very low solubility of polythioesters. Some thermal, mechanical, and electrical properties of the products have been determined. Products of dimercaptan with the terephthaloyl and isophthaloyl chlorides show the best properties.  相似文献   

16.
The solubilities of solid 2,3-dimethylbutane and cyclopentene in liquid argon at a temperature of 87.3 K and in liquid nitrogen at 77.4 K have been measured by the filtration method. The hydrocarbon contents in solutions were determined using gas chromatography. GC–MS was used to identify impurities in solutes. The experimental value of the mole fraction solubility of solid 2,3-dimethyl-butane in liquid argon at 87.3 K is (8.26 ± 1.60) × 10–6 and (2.77 ± 0.94) × 10–8 in liquid nitrogen at 77.4 K. The experimental value of the mole fraction solubility of solid cyclopentene in liquid argon at 87.3 K is (5.11 ± 0.44) × 10–6 and (4.60 ± 0.76) × 10–8 in liquid nitrogen at 77.4 K. The Preston–Prausnitz method was used for calculation of the solubilities of solid hydrocarbons in liquid argon in the temperature range 84.0–110.0 K and in liquid nitrogen from 64.0 to 90.0 K. The solvent–solute interaction parameters l 12 were also calculated. At 90.0 K liquid argon is a better solvent for investigated solid hydrocarbons than is liquid nitrogen.  相似文献   

17.
《Fluid Phase Equilibria》1999,155(2):241-249
Solid–liquid–liquid equilibrium data of the ternary systems water+LiCl+2-butanol, water+LiCl+2-methyl-1-propanol (i-butanol) and water+LiCl+1-butanol have been experimentally determined at 25°C. The equilibrium diagrams determined show differences between the systems. In the system with 1-butanol, the solid phase of the liquid–liquid–solid region is monohydrated salt. However, in the systems with 2-butanol and 2-methyl-1-propanol it is anhydrous salt. With respect to the liquid+liquid zone, the three diagrams are very similar with an unusual S-shaped solubility curve in the organic branch that can be explained depending on whether the organic solvent takes part in the solvation of ions. The more salt, the more numbers of ions solvated by water and organic solvent and the solubility of water and salt in the organic phase increase notably producing the unusual S-shaped solubility curve.  相似文献   

18.
密度法测定了298.15 K下乙醇、环己烷、三氯甲烷、甲苯、丙酮、四氯化碳、乙腈、二甲基甲酰胺、二甲基亚砜在甲醇或苯及两者混合物中的无限稀释偏摩尔体积. 密度测定所用溶液中溶质的浓度范围是0.2一1.5 m; 甲醇和苯混合物是全组成比范围. 溶质偏摩尔体积随甲醇-苯组成比的变化趋势反映了几种分子间相互作用结果即三种分子间物理型分子间相互作用; 溶质与甲醇分子氢键缔合相互作用; 溶质同甲醇或苯的弱络合作用。  相似文献   

19.
The solubilities of 1-pentene ice in liquid nitrogen at a temperature of 77.4 K and in liquid argon at 87.3 K have been measured by the filtration method. The 1-pentene content in solution was determined using gas chromatography. The experimental value of the mole fraction solubility of 1-pentene ice in liquid nitrogen at 77.4 K is: (1.28±0.25)×10–7 and (4.11±0.44)×10–7 in liquid argon at 87.3 K. The Preston–Prausnitz method was used for calculation of the solubilities of 1-pentene ice in liquid nitrogen in the temperature range 64.0–90.0 K and in liquid argon in the temperature range 84.0–90.0 K. The parameters l 12 were also calculated. At 90.0 K liquid argon is the better solvent for 1-pentene ice than is liquid nitrogen.  相似文献   

20.
测定了RbNO3-C2H5OH-H2O 体系在25 ℃和50 ℃的等温平衡溶解度及饱和液的性质(密度和折光率). 绘制了相图, 计算了盐析率, 评价了盐析效果. 用经验公式分别对溶解度、密度和折光率进行了关联, 效果良好. 体系没有产生分层现象, 得到的平衡固相皆为无水铷盐, 没有新化合物或水合物生成.  相似文献   

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