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1.
Phase equilibria and critical phenomena in the potassium nitrate-water-n-butoxyethanol ternary system were studied by the visual polythermal method over the temperature range 10–150°C. In this system, the boundary binary liquid system is characterized by the presence of a closed stratification region. The temperature of the formation of a critical tie line of monotectic equilibrium (18.3°C) and solution compositions corresponding to the critical solubility points at various temperatures were determined. The n-butoxyethanol distribution coefficients between the aqueous and organic phases of the monotectic state were calculated at eight temperatures. n-Butoxyethanol salting out from aqueous solutions by potassium nitrate increased as the temperature grew. The generalized scheme of topological transformations of salt-binary solvent ternary system phase diagrams with salting out was substantiated and augmented.  相似文献   

2.
Phase equilibria and critical phenomena in the potassium nitrate—water—diethylamine ternary system were studied by the visual polythermal method over the temperature range 40–150°C. The corresponding boundary binary liquid system was characterized by stratification with the lower critical temperature of solution. The introduction of potassium nitrate into the water—diethylamine system lowered its lower critical temperature of solution from 146.1 to 48.1°C and decreased the mutual solubility of the components. The diethylamine distribution coefficients between the aqueous and organic monotectic equilibrium phases at various temperatures were calculated. The effect of the salting out of diethylamine from aqueous solutions under the action of potassium nitrate was found to strengthen as the temperature increased. The constructed isotherms of the phase states of the system substantiated the generalized topological scheme of the transformation of phase diagrams of salt-binary solvent ternary systems with salting out.  相似文献   

3.
Phase equilibria and critical phenomena were studied from -5 to 120°C in the rubidium nitrate-water-acetonitrile system, in which the liquid binary subsystem is characterized by liquid-liquid phase separation with an upper critical solution point (UCSP), using a visual polythermal method. We found that rubidium nitrate has a salting out effect on water-acetonitrile solutions and causes them to demix at any temperature in the specified range. Acetonitrile distribution coefficients between aqueous and organic monotectic phases were calculated for various temperatures. The minimum value was observed for 20.0°C. Six isothermal phase diagrams of the system were plotted to verify a fragment of the global scheme of the topological transformation of phase diagrams for salt-binary solvent ternary systems with salting out. The salting out effects of potassium, rubidium, and cesium nitrates on water-acetonitrile mixtures were comparatively analyzed.  相似文献   

4.
Phase equilibria and critical phenomena in the cesium nitrate-water-diethylamine ternary system were studied by the visual-polythermal method over the temperature range 60–150 °C, where the boundary binary liquid system was characterized by stratification with a lower critical solution temperature (LCST). The introduction of cesium nitrate into the water-diethylamine system decreased the LCST of this system from 146.1 to 69.3°C and lowered the mutual solubility of the components. The diethylamine distribution coefficients between the aqueous and organic phases were calculated for monotectic equilibria at various temperatures. The salting out of diethylamine with cesium nitrate grew stronger as the temperature increased. The conclusion was drawn that the isotherms of the phase states of the system substantiated the generalized scheme of topological transformations of phase diagrams for salt-binary solvent ternary systems with salting out. The salting out effects of cesium and potassium nitrates on the water-diethylamine binary system were compared.  相似文献   

5.
Phase equilibria and critical phenomena in the cesium nitrate-water-isopropanol system, where the liquid binary subsystem does not separate over the entire temperature range of its liquid state, were studied within 70–120°C using visual polythermal analysis. The temperature at which the monotectic critical tie-line appears (79.0°C) and the compositions of the solutions at critical solution points at various temperatures were determined. Isopropanol distribution coefficients between aqueous and organic monotectic phases were calculated for five temperatures. The salting out of isopropanol by cesium nitrate from aqueous solutions is enhanced by temperature elevation. The phase isotherms validated a previously reported fragment of the general scheme of the topological transformation of ternary phase diagrams for salt-binary solvent systems with salting out. Original Russian Text ? D.G. Cherkasov, V.F. Kurskii, S.I. Sinegubova, K.K. Il’in, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 6, pp. 1032–1036.  相似文献   

6.
In the ternary system cesium nitrate-water-acetonitrile, in which liquid-liquid phase separation with an upper critical solution point (UCSP) exists in the liquid binary subsystem, was studied in the range from ?5 to 120°C using visual polythermal analysis. Liquid-liquid phase separation in the ternary system is observed above 96.0°C and below 2.8°C. Acetonitrile distribution coefficients between the aqueous and organic phases of monotectic equilibrium were calculated for various temperatures. Phase isotherms of the system confirm the general scheme of the topological transformation of phase diagrams in salt-binary solvent ternary systems with salting out.  相似文献   

7.
The solubilities of components, phase equilibria, and critical phenomena in the cesium nitrate–water–pyridine ternary system are studied in the 5–100°C temperature range by the visual–polythermal method. Cesium nitrate is found to exhibit a salting-out effect at temperatures above 79.9°C causing phase separation in homogeneous water–pyridine solutions. The temperature of formation of the critical monotectic tie line (79.9°C) and the compositions of solutions corresponding to the liquid–liquid critical points at three temperatures are determined. The pyridine distribution coefficients between the aqueous and organic phases of the monotectic state at 85.0, 90.0, and 100.0°C are calculated. Their values demonstrate that salting-out of pyridine from aqueous solutions by cesium nitrate increases at higher temperatures. The plotted isotherms of phase diagrams confirm the fragment of the scheme of topological transformation of the phase diagrams of salt–binary solvent ternary systems with salting-in and salting-out phenomena.  相似文献   

8.
Phase equilibria and critical phenomena in the potassium perchlorate-water-n-butoxyethanol ternary system, where the boundary liquid binary system is characterized by the presence of a closed stratification region, were studied by the visual-polythermal method over the temperature range 40–150°C. The temperature of the formation of the critical monotectic equilibrium tie line (141.0°C) and temperature dependences of the compositions of mixtures corresponding to the critical solubility points of the stratification region over the temperature ranges 47.7–130.3 and 141.0–150.0°C were determined. The isotherms of phase states constructed at 10 temperatures were used to reveal the topological transformation of the phase diagram of the ternary system depending on temperature. At low concentrations (up to 5.8 wt %), potassium perchlorate had a salting in action on heterogeneous water-n-butoxyethanol mixtures. The solubility of the salt increased as the temperature grew, and, above 141.0°C, potassium perchlorate had a salting out action. The salting out of n-butoxyethanol from aqueous solutions by potassium perchlorate grew stronger as the temperature increased.  相似文献   

9.
Phase equilibria and critical phenomena in a potassium perchlorate-water-tetrahydrofuran ternary system are studied by visual polythermal means in the range of 40 to 140°C; the solubility diagram of the liquid subsystem is characterized by the presence of isolated binodal curve. The temperature of formation for the critical node of the monotectic state (107.3°C) and the dependences of the composition that corresponds to the critical points of solubility in the delayering field vs. temperature in the ranges of 70.3 to 107.3°C and 137.1 to 140.2°C are determined. The topological transformation of the investigated ternary system’s phase diagram upon a change in temperature is studied using isothermal sections of the system’s temperature concentration prism, plotted at nine temperatures. It is found that potassium perchlorate has only a salting-in effect on mixtures of water and tetrahydrofuran at temperatures below 107.3°C; at higher temperatures, it has both a salting-in and a salting-out effect, depending on its concentration and the composition of mixed solvent. It is shown that potassium perchlorate’s effect of salting tetrahydrofuran out of aqueous solutions grows slightly with an increase in temperature.  相似文献   

10.
The phase equilibria and critical phenomena in a sodium nitrate—water—diethylamine ternary system were studied by the visual polythermal method at 10—150°C, where the frontier binary liquid system is characterized by delamination with the lower critical solution temperature (LCST). The introduction of sodium nitrate into the water—diethylamine system led to a significant decrease (from 146.1 to 22.9°C) in the LCST of the system and the mutual solubility of its components. The coefficients of the distribution of diethylamine between the water and organic phases of the monotectic equilibrium at different temperatures were calculated. The effect of the salting-out of diethylamine by sodium nitrate from aqueous solutions increased with temperature. The constructed isotherms of the phase states of the system confirmed the general scheme of the topological transformation of the phase diagrams of the salt—binary solvent ternary systems with salting-out. The results of the salting-out action of sodi um, potassium, and cesium nitrates on the water—diethylamine binary system were compared.  相似文献   

11.
Phase equilibria and critical phenomena in the lithium nitrate-water-acetonitrile ternary system were studied by a visual polythermal method within the range of ?20 to 50°C. In this ternary system, the constituent liquid binary system is characterized by phase separation with an upper critical solution temperature. It was found that the ternary system undergoes phase separation at temperatures below 0.7°C. In the phase diagram within the range of ?1.1 to 0.7°C, a closed phase separation region with two critical points was revealed. The temperature of the formation of the critical tie line of the monotectic state the solid phase of which is the crystalline hydrate LiNO3 · 3H2O was determined (?18.7°C). Depending on the concentration, lithium nitrate has both salting-in and salting-out effect on aqueous acetonitrile mixtures. The plotted isothermal sections of the temperature-concentration prism of the system at fifteen temperatures showed the pattern of the topological transformation of its phase diagram with varying temperature.  相似文献   

12.
The results of a polythermal study of the salting out action of alkali metal (Na, K, and Cs) nitrates on the water-diethylamine binary system characterized by stratification with a lower critical solution point (LCSP) were comparatively analyzed. Alkali metal nitrates experiencing homoselective solvation in aqueousorganic solvents were found to decrease the LCSP of this binary system, that is, have a salting out action. A decrease in the radius of the cation in the series CsNO3-KNO3-NaNO3 decreased the temperature of critical tie line formation in the monotectic state of salt-water-diethylamine ternary systems (69.3, 48.1, and 22.9°C, respectively). In all ternary systems, first and foremost in the system with potassium nitrate, the effect of diethylamine salting out from aqueous solutions grew stronger as the temperature increased. The conclusion was drawn that, among the salts studied, sodium nitrate had the strongest salting out effect at 22.9–88.4°C, and potassium nitrate, at 88.4–150.0°C.  相似文献   

13.
Phase equilibria and critical phenomena in a cesium nitrate-water-triethylamine system in which the constituent binary liquid system is stratified at the lower critical solution temperature (LCST) is studied in a range of 5–25°C by the visual polythermal method. It is found that introducing cesium nitrate into the water-triethylamine system leads to a slight reduction in the LCST (from 18.3 to 16.3°C) and to a decrease in the mutual solubility of the components. The distribution coefficients of triethylamine between aqueous and the organic phases of the monotectic state at different temperatures are calculated. It is found that the salting-out of triethylamine from aqueous solutions by cesium nitrate increases with rising temperature. The results of the salting-out effect of sodium, potassium, and cesium nitrates on a water-triethylamine binary system are compared.  相似文献   

14.
The solubility of components and critical phenomena in the ternary system constituted by potassium nitrate, water, and n-propyl alcohol were studied by the visual polythermal method in the temperature range 25–80°C. The temperature of formaiton of the critical node of the monotectic equilibrium (critical solution-solid phase) and the solution compositions corresponding to the critical solution points at different temperatures were determined. The isothermal solubility diagrams of the system were constructed and the distribution coefficients of n-propyl alcohol at different temperatures were calculated. A comparative analysis of the salting-out effect exerted by potassium nitrate on aqueous solutions of n-propyl alcohol and isopropyl alcohol was done.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 3, 2005, pp. 398–402.Original Russian Text Copyright © 2005 by Sinegubova, Cherkasov, Il’in.  相似文献   

15.
The salting-out effects of sodium, potassium, and cesium nitrates on the water-isopropanol system, which is homogeneous throughout its liquid-state temperature range, are compared at different temperatures. The alkali-metal nitrates, which undergo homoselective solvation in aqueous-organic solvents, exert a salting-out effect on aqueous isopropanol. As the crystallographic radius of the cation decreases in the order CsNO3-KNO3-NaNO3, the monotectic critical tie line temperature for the salt-water-isopropanol system decreases (79.0, 47.2, and 6.1°C, respectively). In each ternary system, the salting-out effect on isopropanol strengthens with an increasing temperature, particularly in the system containing sodium nitrate. Among the salts examined, the strongest salting-out effect between 6.1 and 90.0°C is produced by sodium nitrate.  相似文献   

16.
The solubility of components and critical phenomena in a ternary system constituted by potassium nitrate, water, and isopropyl alcohol were studied by the visual-polythermic method in the temperature range 25–90°C. The formation temperature of the critical node of the monotectic equilibrium (critical solution—solid phase) and the solution compositions corresponding to the critical solubility points at different temperatures were determined. Isothermal solubility diagrams of the system were constructed, the previously suggested scheme of the topological transformation of the phase diagrams of ternary stratifying systems constituted by a salt and a binary solvent was confirmed, and the distribution coefficients of isopropyl alcohol at different temperatures were calculated.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 12, 2004, pp. 1945–1949.Original Russian Text Copyright © 2004 by Sinegubova, Ilin, Cherkasov, Kurskii, Tkachenko.  相似文献   

17.
A truly miscible ternary miscible blend consisting of poly(?‐caprolactone) (PCL), poly(phenyl methacrylate), and poly(benzyl methacrylate) (PBzMA) was discovered. The three‐polymer blend system was completely miscible within the entire composition range at ambient temperature up to about 150 °C, and ternary phase diagrams at increasing temperatures were characterized and interpreted. A ternary‐interaction model based on the modified Flory–Huggins expression was used to describe the phase diagrams with the individual binary interaction strengths. The model fitted well with the experimental‐phase diagram for the ternary blend system at T = 250 °C, where the binary PCL‐PBzMA blend system is on the critical points of phase separation. Interpretation of discrepancy between the model and experimental at other temperatures was handled with an empirical approach. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 747–754, 2002  相似文献   

18.
A visual polythermal method is used to study the mutual solubility of components and critical phenomena in a ternary system of cyclohexane-pyridine-acetic acid in the 10.0–55.0°C range. It is noted that the isothermal solubility diagrams of the system in the 10.0–52.5°C range is characterized by the occurrence of a closed separation region. A temperature dependence of the mixture composition, which corresponds to the critical point of solubility, is determined. It is found that with the increase in the temperature a two-liquid phase region disappears through a non-critical point.  相似文献   

19.
By visual-polythermal method in the range 5–25°C we studied phase equilibria and critical phenomena in a ternary system potassium nitrate-water-triethylamine, where its component, binary liquid system, is stratified at the lower critical solution temperature.  相似文献   

20.
Visual-polythermal method was used to study, in the temperature range from ?17 to 25°C, the phase equilibria and critical phenomena in the ternary system constituted by sodium nitrate, water, and triethanolamine, in which the boundary binary system is characterized by stratification with a lower critical solution point.  相似文献   

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