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1.
The solubilities of solid pentane, 2-methylbutane (isopentane), and cyclopentane in liquid argon at 87.3 K have been measured by the filtration method. The C5 hydrocarbon content in solution was determined using gas chromatography. The solubilities of the C5 hydrocarbons in liquid argon at 87.3K vary from 0.61 × 10–7 mole fraction for cyclopentane, to 1.37 × 10–7 mole fraction for pentane, and 8.83 × 10–6 mole fraction for 2-methylbutane. The Preston–Prausnitz method was used for calculation of the solubilities of solid C5 hydrocarbons in liquid argon in the temperature range 84–110 K and in liquid nitrogen in the range 64–90K. The values of the solvent–solute interaction constant l 12 were also calculated.  相似文献   

2.
The solubilities of solid hexane and cyclohexane in liquid argon at 87.3 K have been measured by the filtration method. The hexane and cyclohexane content in solution was determined using gas chromatography. The solubilities of the C6 hydrocarbons in liquid argon at 87.3 K are (0.56 ± 0.11) × 10-7 mole fraction for hexane and (1.04 ± 0.30) × 10-7 mole fraction for cyclohexane. The Preston–Prausnitz method was used for calculation of the solubilities of solid hexane and cyclohexane in liquid argon in the temperature range 84–110 K. The values of the solvent–solute interaction constant l12 were also calculated.  相似文献   

3.
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   

4.
The solubility of solid 2-methyl-1,3-butadiene (isoprene) in liquid argon at a temperature of 87.3 K and in liquid nitrogen at 77.4 K has been measured by the filtration method. The hydrocarbon contents in solutions were determined using gas chromatography. GC–MS was used to identify impurities in the solute. The experimental value of the mole fraction solubility of solid isoprene in liquid argon at 87.3 K is (1.41 ± 0.27) × 10–6 and (1.56 ± 0.36) × 10–7 in liquid nitrogen at 77.4 K. The Preston–Prausnitz method was used for calculation of the solubilities of solid hydrocarbon 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 isoprene than is liquid nitrogen. The experimental values of the solubilities of isoprene in liquid argon and nitrogen were compared with results obtained for selected unsaturated and aromatic hydrocarbons.  相似文献   

5.
The solubilities of solid 1-hexyne in liquid argon at 87.3 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 1-hexyne. The experimental value of the mole fraction solubility of solid 1-hexyne in liquid argon at 87.3 K is (0.85 ± 0.19) × 10–7 and (1.25 ± 0.08) × 10–8 in liquid nitrogen at 77.4 K. The Preston–Prausnitz method was used for calculation of the solubilities of solid hydrocarbon 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 solid 1-hexyne than is liquid nitrogen.  相似文献   

6.
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   

7.
Two ternary systems comprising gasoline components were characterized by determining their refractive indexes, densities, sound transmission speeds, and isentropic compressibilities at 25°C and 1 atm pressure. These data were then correlated with composition using a polynomial. Single measurements of the refractive index and density of fully miscible mixtures of the system 2-methoxy-2-methylbutane (TAME) + methanol + 2,2,4-trimethylpentane allowed estimation of its composition with precision better than ±0.002 mole fraction. However, it was shown that this approach to compositional analysis of homogeneous mixtures of TAME + methanol + methylcyclohexane would not give reliable results.  相似文献   

8.
The solubility of nitrogen in pure liquid water was measured in the pressure range 45 to 115 kPa and in the temperature range 5 to 50°C. These data are used to obtain Henry coefficients H 2,1 (T,P s,1 ) at the vapor pressure P s,1 of water. The temperature dependence of H 2,1 (T,P s,1 ) is accounted for by both a Clarke-Glew (CG) type fitting equation, and a power series in T–1, as suggested by Benson and Krause (BK). The imprecision of our measurements is characterized by an average deviation of ±0.038% from a four-term CG equation, and by an average deviation of ±0.042% from a three-term BK equation. From the temperature variation of H 2,1 (T,P s,1 ) partial molar quantities referring to the solution process, such as enthalpies and heat capacities of solution, are obtained. They are given in tabular form, together with H 2,1 (T,P s,1 ) and derived Ostwald coefficients L, at rounded temperatures. Finally, experimental results are compared with values calculated via scaled particle theory.  相似文献   

9.
The solubility of SO2 and CO2 in dimethyl sulfoxide has been determined in the temperature range from 293.15 to 313.15?K and partial pressure of SO2 from 0.15 to 2.62?kPa, and the partial pressure of CO2 from 5 to 18?kPa. A solubility model is proposed and the solubilities calculated by the model show good agreement with the experimental data.  相似文献   

10.
The stable phase equilibria of quaternary systems LiBr-NaBr-MgBr2-H2O and LiBr-KBr-MgBr2-H2O at 298.15 K were studied by both experimental measurement(isothermal solution saturation method) and theoretical prediction(Pitzer model). The solubilities of the saturated solution have been determined experimentally and two stable phase diagrams and relevant water diagrams of the two quaternary systems were obtained. Results show that quaternary system LiBr-NaBr-MgBr2-H2O is hydrate II type as NaBr and NaBr·2H2O coexistence. Its phase diagram consists of only one invariant point, four univariant curves, and five crystallization fields. The quaternary system LiBr-KBr-MgBr2-H2O is a complex type as the double salt KBr·MgBr2·6H2O formed. In addition to this double salt, the three single salts LiBr·2H2O, KBr and MgBr2·6H2O also crystallize. In this paper, the solubilities of phase equilibria in above quaternary systems were also calculated by the Pitzer's electrolyte solution model. All the needed parameters can be obtained from the literature or be fitted by experimental data. On the Basis of the experimental and calculated results, the phase diagram of the quaternary system was plotted for comparison. It shows that the calculation results are consistent with the experimental ones.  相似文献   

11.
Experimental liquid–liquid phase diagrams are presented for the multicomponent systems isooctane–benzene–(80 mass% methanol + 20 mass% water)–5 mass% isobutyl alcohol (2-methyl-1-propanol) and isooctane–benzene–(80 mass% methanol + 20 mass% water)–15 mass% isobutyl alcohol, at 298.15 K. The density and interfacial tension of conjugate phases of concentration located in the isothermal binodal have been determined at 298.15 K for the partially miscible systems: isooctane–benzene–methanol, isooctane–benzene–(80 mass% methanol + 20 mass% water), isooctane–benzene–(80 mass% methanol + 20 mass% water)–5 mass% isobutyl alcohol, and isooctane–benzene–(80 mass% methanol + 20 mass% water)–15 mass% isobutyl alcohol. The experimental tie-line data define the binodal or coexistence curve of the two studied multicomponent systems and depending on the initial isobutyl alcohol concentration the liquid–liquid phase diagram is either of type II, with low alcohol concentration, or type I, with high concentration of alcohol, which is a clear indication that the solubility of the partially miscible systems is greatly enhanced via the co-solvency phenomenon. It is observed that both the density of each conjugate phase and the interfacial tension of each tie-line are valuable indicators of the degree of solubility of the multicomponent systems. Furthermore the experimental tie-lines data were correlated with the NRTL and UNIQUAC solution models with satisfactory quantitative results.  相似文献   

12.
The cavity formation energy (CFE) is the free energy invested in rearrangement of the solvent molecules when a solute is inserted into a solvent, which is very important to the solubility studies. The CFE of liquid solvents; n-heptane, n-octane, cyclohexane, tetrachloromethane, benzene and water at 298.15 K has been determined. The solubility (in terms of Henry’s law constant), Gibb’s free energy of solution and ΔGs*, the thermodynamical quantities for the solvation process defined by Ben-Naim and Marcus of fluorine containing gases; freon-11, freon-12, freon-13, freon-14, freon-21, freon-c-318 and sulpherhexafluoride (SF6) in above liquid solvents at 298.15 K also been calculated with this cavity formation energy. It yields good agreement with experimental results. The calculation shows importance of CFE in determining the solution properties.  相似文献   

13.
摘要:利用过渡金属镉(锌)盐与1,5-二(2-乙基咪唑)戊烷(BEIP)、5-羟基间苯二甲酸(5-OHH2IP)在水热条件下合成了配合物[Cd(BEIP)(Cl)2]n1)和[Zn(BEIP)(5-OHIP)]n2),并对其进行了元素分析、IR及X射线衍射法表征。晶体结构研究表明:配合物1属于正交晶系,Pca21空间群。配合物2属于单斜晶系,P21/n空间群,β=100.542(4)°。配合物1是由配体1,5-二(2-乙基咪唑)戊烷连接镉离子形成一维链状结构。而配合物2是由配体间苯二甲酸连接锌离子形成一维链状结构,该一维链通过1,5-二(2-乙基咪唑)戊烷连接成二维网络结构,进而通过氢键连接成三维超分子结构。此外,配合物12具有较高的稳定性和较好的荧光性能,配合物2对甲基橙染料有一定的降解作用。  相似文献   

14.
15.
In an analysis of the solubility of a wide range of phthalocyanines (Pcs) and its analogues (SubPcs) in liquid and/or supercritical CO2, compounds with trifluoroethoxy substituents were found to exhibit high solubility. To our knowledge, this is the first example of Pc compounds soluble in 100% CO2. This unprecedented unique property of trifluoroethoxy substituted Pcs might have particular applications in catalysis in organic reactions as well as dyes for solar cells by CO2 delivering coatings.  相似文献   

16.
The thermodynamic statistical model based on the distribution of molecular populations among energy levels has been employed for the analysis of the solubility of hydrocarbons and other inert gases or liquids in water at different temperatures. The statistical distribution is described by a convoluted partition function ZG·s. The product of a grand canonical partition function ZG represents the distribution of the species in the reaction while the canonical partition function ZG represents the properties of the solvent. The first derivative of the logarithm of the partition function with respect to 1/T is the apparent enthalpy which is the result of the contributions of the separate partition functions, {Haap}T=Ho+nwCp,wT, where {Happ}T refers to ZG, nwCp,wT=–Hw to s, and Ho is the change in enthalpy of hydrocarbon-water reaction. The plot {Happ}T vs/ T results in a straight line with slope nw at constant Cp,w. The apparent enthalpy is obtained from the coefficients of the polynomial fitting of the solubility data, as a function of 1/T. Alternatively, the apparent enthalpy can be determined calorimetrically. The enthalpy thus obtained is a linear function of the Kelvin temperature. The values of nw range from 1.6, 1.9, 5.6 to 5.8 for helium, hydorgen, butane and hexane, respectively. For fluorocompounds the range of nw is 10.1 to 11.1 indicating that nw is a function of the number of water molecules expelled from the cage of solvent to form a cavity to host the solute molecule. The analysis of several sets of calorimetric or solubility data with the present molecular thermodynamic model yields values of Ho and nw consistent with the size of the dissolved molecules.List of Symbols p pressure - H ij average enthalpy - H i level enthalpy (=H) - H i enthalpy difference - H ij intersublevel energy difference - i index of level - j index of sublevel - ZG grand canonical partition function - S canonical partition function - ZG- convoluted partition function - –G o/RT standard Gibbs energy normalized toRT - –H o/RT standard enthalpy normalized toRT - S o/R standard entropy normalized toR - C p molar heat capacity - T absolute temperature - H G- enthalpy of the convoluted ensemble - H G enthalpy of the solute - H enthalpy of the solvent - H app apparent enthalpy - H w enthalpy of water - CyHz hydrocarbon - W water - K s solubility equilibrium constant - x 2 molar fraction of solute - CyHzW(x-nw) hydrocarbon molecule trapped in a cavity - K H Henry constant - P s solubility product - [W] concentration of water - reference temperature - a, b, c, d coefficients of the fitting polynomial - {H app}T apparent enthalpy at temperatureT - {H }T standard enthalpy at temperatureT - {H w}T water contribution to enthalpy at temperatureT - C p,w isobaric molar heat capacity of water - L Ostwald coefficient - C p isobaric heat capacity difference - Bunsen coefficient - C p,app apparent isobaric heat capacity difference - n C number of carbon atoms in the chain - h w interaction enthalpy of one water molecule - H 0 intercept for the extrapolated enthalpy  相似文献   

17.
18.
利用过渡金属镉(锌)盐与1,5-二(2-乙基咪唑)戊烷(BEIP)、5-羟基间苯二甲酸(5-OHH2IP)在水热条件下合成了配合物[Cd(BEIP)(Cl)2]n1)和[Zn(BEIP)(5-OHIP)]n2),并对其进行了元素分析、IR及X射线衍射法表征。晶体结构研究表明:配合物1属于正交晶系,Pca21空间群。配合物2属于单斜晶系,P21/n空间群,β=100.542(4)°。配合物1是由配体1,5-二(2-乙基咪唑)戊烷连接镉离子形成一维链状结构。而配合物2是由配体间苯二甲酸连接锌离子形成一维链状结构,该一维链通过1,5-二(2-乙基咪唑)戊烷连接成二维网络结构,进而通过氢键连接成三维超分子结构。此外,配合物12具有较高的稳定性和较好的荧光性能,配合物2对甲基橙染料有一定的降解作用。  相似文献   

19.
系统研究了1,2-丙二醇+MCl (M=Na, K, Rb, Cs)+H2O三元体系在298.15 和308.15 K时的等温相平衡. 采用硝酸汞滴定法测定了体系中无机盐的含量, 采用安东帕RXA170 折光率仪及DMA4500 密度计测定了所有体系的折光率和密度数值. 报道了1,2-丙二醇质量分数从0增加到0.9过程中饱和及不饱和三元溶液体系的等温溶解度、密度和折光率数据. 实验结果发现, 随着1,2-丙二醇的不断加入, 饱和溶液的溶解度和密度均呈现出减小的趋势, 而折光率的变化则呈现出相反的趋势. 采用经验方程关联了不同醇水比条件下不饱和溶液的密度和折光率实验数据, 获得了较为理想的拟合结果. 本研究的开展充实了碱金属盐在混合溶剂中的热力学数据, 为相关溶液化学研究奠定了基础.  相似文献   

20.
Solubility measurements of sulfur compounds in supercritical fluids are required in order to determine the feasibility of supercritical extraction for removing them from gasoline and diesel fuel. In this work, solubility of thiophene in CO2 and in CO2 + 1-propanol mixtures were measured from 313 to 363 K using an apparatus based on the static–analytical method. Vapor–liquid equilibria (VLE) data of binary mixtures were fitted to the Peng–Robinson equation of state (EoS) with classical mixing rules. The binary interaction parameters (kij) obtained were used to predict the VLE data of ternary systems. The calculated values given by this simple model agree well to the experimental data.  相似文献   

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