4-羟基苯甲醛及其溴代物在氯仿中溶解度测定和关联

Solubilitees of 4-hydroxybenzaldehyde,3-bromo-4-hydroxybenzaldehyde,3,5-dibromo-4-hydroxybenzaldehyde in chloroform were messured at temperatures ranging from 283.15K to 323.15K.The measurements of temperature and enthalpy of fusion of pure solutes were used for caculation of solubility by ideal solution model,which was higher than the experimental values.The very low solubility in chloroform was due to self association of solute molecules,A λh formula was used to fit the data and had shown good correlation results.     

Experimental measurement and thermodynamic modeling of binary and ternary solid-liquid phase equilibrium for the systems formed by L-arabinose,D-xylose and water

Solid-liquid phase equilibrium data for binary (L-arabinose-water) and (D-xylose-water) systems at temperatures from (269.85-298.05) K and ternary (L-arabinose-D-xylose-water) system at temperatures of 273.85 K,278.85 K and 284.45 K were measured at atmospheric pressure.The ternary phase diagrams of the systems were constructed on the base of the measured solubility.Two pure solid phases were formed at given temperatures,including pure L-arabinose and pure D-xylose,which were confirmed and determined by the method of Schreinemakers' wet residue.At the same temperature,the crystallization region of L-arabinose was larger than D-xylose's.The acquired solubility data were then correlated using the NRTL model,Wilson model and Xu model.The calculated solubility with the three models agreed well with the experimental values.     

Measurement and correlation for solubility of diosgenin in some mixed solvents简

The solubility data of diosgenin in mixed systems of ethanol ＋ 1-propanol （1 ： 1）, ethanol ＋ 1-butanol （1 ： 1）, ethanol ＋ isobutyl alcohol （1 ： 1）, methanol ＋ isobutyl alcohol （1 ： 1）, methanol ＋ isobutyl alcohol （1 ： 4）, ethanol ＋ 1-pentanol （1 ： 1） and carbon tetrachloride were measured over the temperature range from 289.15 K to 334.15 K by a laser monitoring observation technique at atmospheric pressure, with all mixtures mixed by volume ratio. The Apelblat equation, the ideal solution model, and the 2h equation are used to correlate the solubility data. The results show that the three models agree well with the experimental data, providing essential support for industrial design and further theoretical study.     

Physicochemical properties of aqueous solutions of sodium glycinate in the non-precipitation regime from 298.15 to 343.15 K

The physicochemical properties, including the density, viscosity, and refractive index of aqueous solutions of sodium glycinate as a solvent for CO2 absorption in the non-precipitation regime were measured under the wide temperature range of 298.15 to 343.15 K. The concentration of the sodium glycinate in an aqueous form in the non-precipitation regime was identified up to 2.0 mol·L?1. The coefficients of thermal expansion values were estimated from measured density data. It was found that, the densities, viscosities and refractive indices of the aqueous sodium glycinate decrease with an increase in temperature, whereas with increasing sodium glycinate concentration in the solution, all three properties increase. Thermal expansion coefficients slightly increase with rising temperature and concentration. The measured values of density, viscosity and refractive index were correlated as a function of temperature by using the least squares method. The predicted data obtained from correlation equations for all measured properties were in fairly good agreement with the experimental data.     

EFFECTS OF ENTRAINERS ON THE PHASE EQUILIBRIUM OF SUPERCRITICAL FLUID EXTRACTION PROCESS

A flow apparatus was set up for measuring the solubility of a solid solute in a supercritical fluid withthe presence of a small amount of entrainer.The solubilities of biphenyl,diphenylamine and benzoic acid insupercritical carbon dioxide with one of the selected entrainers which were ethanol,acetone and n-hexanerespectively,were obtained in the pressure range of 10—32 MPa and the temperature range of 308—318K.Asolvolytic association theory has been proposed to explain the mechanism of entrainer effect,and theexperimental results were reasonably analysed.According to the solvolytic association theory,the association equa-tion of state was adopted to correlate the experimental data with good accuracy.     

取代苯甲酸类化合物在正辛醇中的固液平衡

The solid-liquid equilibrium of benzoic acid derivatives in 1-octanol was first determined in this article. Using a laser monitoring observation technique, the solubility data of o-amino-benzoic acid, p-amino-benzoic acid,o-chloro-benzoic acid, and m-nitro-benzoic acid in 1-octanol were measured by the polythermal method in the temperature range of 20-50℃. The experimental data were regressed with the. Wilson equation and the λH equation. The experimental results showed that the solubility of the four chemicals in 1-octanol increased significantly with temperature. The results indicate that the molecular structure and interactions affect the solubility significantly.The solubility order of the benzoic acid derivatives is as follows： m-nitro-benzoic acid〉o-chloro-benzoic acid〉 o-amino-benzoic acid〉p-amino-benzoic acid. Both the Wilson equation and λH equation are in good agreement with the experimental data.     

Determination and correlation solubility of m-phenylenediamine in (methanol,ethanol, acetonitrile and water) and their binary solvents from 278.15 K to 313.15 K

In this study, the solubility of m-phenylenediamine in four pure solvents(methanol, ethanol, acetonitrile and water) and three binary solvent(methanol + water),(ethanol + water) and(acetonitrile + water) systems were determined in the temperature ranging from 278.15 K to 313.15 K by using the gravimetric method under atmospheric pressure. In the temperature range of 278.15 K to 313.15 K, the mole fraction solubility values of m-phenylenediamine in water, methanol, ethanol, and acetonitrile are 0.0093–0.1533, 0.1668–0.5589,0.1072–0.5356, and 0.1717–0.6438, respectively. At constant temperature and solvent composition, the mole fraction solubility of o-phenylenediamine in four pure solvents was increased as the following order:water b ethanol b methanol b acetonitrile; and in the three binary solvent mixtures could be ranked as follows:(ethanol + water) b(methanol + water) b(acetonitrile + water). The relationship between the experimental temperature and the solubility of m-phenylenediamine was revealed as follows: the solubility of mphenylenediamine in pure and binary solvents could be increased with the increase of temperature. The experimental values were correlated with the Jouyban–Acree model, van't Hoff–Jouyban–Acree model, modified Apelblat–Jouyban–Acree model, Sun model and Ma model. The standard dissolution enthalpy, standard dissolution entropy and the Gibbs energy were calculated based on the experimental solubility data. In the binary solvent mixtures, the dissolution of m-phenylenediamine could be an endothermic process. The solubility data,correlation equations and thermodynamic property obtained from this study would be invoked as basic data and models regarding the purification and crystallization process of m-phenylenediamine.     

A MATHEMATICAL MODEL AND SIMULATION FOR NON ISOTHERMAL GAS ABSORPTION WITH CHEMICAL REACTION

In this paper, the principles of mass and heat transfer for a non-isothermal gas absorption with chemical reaction have been described. The examples of carbon monoxide complexing with aluminum cuprous tetrachloride solution and carbon dioxide absorbed by monoethanolamine aqueous solution in packed column have been simulated and computed with a mathematical model which considered of both mass and heat transfer, gas and liquid resistance. The fundamental differential equations of the process are treated with forth order Runge-Kutta method. Through simulating and computing, the temperature profiles and concentration profiles of both gas and liquid phase along the packed height have been visualized. The results are reasonably accurate and conform with pilot plant experimental data.     

疏水缔合聚合物在搅拌槽中的溶解特性

Enhanced oil recovery (EOR) by means of polymer flooding is an important technology for the strategic development of offshore oilfields in China. Hydrophobically associating polyacrylamide (HAPAM) has been recently proposed as a new flooding agent. The solubility of HAPAM is low, which is the bottleneck for further improving the oil recovery through polymer flooding in offshore oilfield. Stirred tanks have been used on offshore platforms to enhance HAPAM dissolving. But there is little literature on the study of HAPAM dissolving characteristics in stirred tanks. In this paper, effects of temperature, salinity, stirring speed, impeller type and stirring method on the dissolution of HAPAM are reported. The experimental results manifest that the dissolving rate of HAPAM increases with temperature and stirring speed, but the viscosity of the polymer solution decreases. There is an optimal range of salinity for polymer dissolving. Combining the operation mode of up-pumping with varying stirring speed, hydrofoil impeller can accelerate the dissolution of HAPAM and maintain a high solution viscosity.     

Solubility measurement and thermodynamic properties of sulfamonomethoxine in pure solvents and sulfamonomethoxine hydrate in acetone + water binary solvent at different temperature

The experimental solubility of sulfamonomethoxine in six different pure solvents (methanol,ethanol,1-propanol,l-butanol,ethyl acetate and acetone) and sulfamonomethoxine hydrate in acetone + water mixture solvents were measured from 294.55 K to 362.15 K by a laser dynamic method under atmospheric pressure.Experimental results indicated that the solubility data of sulfamonomethoxine increased with temperature increasing in pure solvents and the solubility followed this order:acetone ＞methanol ＞ ethanol ＞ ethyl acetate ＞ 1-propanol ＞ 1-butanol,but solubility in ethyl acetate was not affected significantly by temperature.In acetone + water mixture solvent,the solubility of sulfa-monomethoxine hydrate increased with temperature and the acetone concentration.Thermodynamic equations were applied to correlate solubility data of sulfamonomethoxine and sulfamonomethoxine hydrate including the modified Apelblat equation,λh equation,Wilson equation,NRTL equation,Van't Hoff-Jouyban Acree equation and modified Apel-Jouyban-Acree equation.Furthermore,thermodynamic properties △Gd,△Hd and △Sd of sulfamonomethoxine and sulfamonomethoxine hydrate in dissolution process were obtained and discussed with the modified Van't Hoff equation and Gibbs equation.     

Solubilities of Isophthalic Acid in Acetic Acid + Water Solvent Mixtures

The solubilities of isophthalic acid (1) in binary acetic acid (2)+water (3) solvent mixtures were determined in a pressurized vessel. The temperature range was from 373.2 to 473.2K and the range of the mole fraction of acetic acid in the solvent mixtures was from x₂ 0 to 1. A new method to measure the solubility was developed, which solved the problem of sampling at high temperature. The experimental results indicated that within the temperature range studied, the solubilities of isophthalic acid in all mixtures showed an increasing trend with increasing temperature. The experimental solubilities were correlated by the Buchowski equation, and the calculate results showed good agreement with the experimental solubilities. Furthermore, the mixed solvent systems were found to exhibit a maximum solubility effect on the solubility, which may be attributed to the intermolecular association between the solute and the solvent mixture. The maximum solubility effect was well modeled by the modified Wilson equation.     

Solubility of 4-(3,4-dichlorophenyl)-1-tetralone in eleven alcohols with the temperature range from 283K to 323K

The solubility of 4-(3,4-dichlorophenyl)-1-tetralone in eleven alcohols (methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 2-propanol, 2-butanol, 2-pentanol, 1,2-propanediol, 1,3-propanediol) was measured by using a laser technique with a temperature range from 283 K to 323 K, and at atmospheric pressure. For mono n-alcohols, the solubility is the lowest in methanol, increasing with the carbon chain of the alcohols. The results were correlated with a semi-empirical equation. The experimental solubility and correlation equation in this work can be used as essential data and models in the purification process of 4-(3,4-dichlorophenyl)-1-tetralone.     

固体─超临界流体相平衡的分子热力学模型

从分子热力学基础出发提出一个适用于固体-超临界流体相平衡的理论模型，溶液中溶质的化学位分解为无限稀溶液化学位及溶质浓度效应两部.无限稀溶液化学位由简化的Oz方程计算，其中包括斥力贡献、局部组成及长程引力项浓度对化学位的贡献由作者根据Kirkwood-Buff溶液理论提出的修正Wilson模型计算．用45个二元系862个数据点对此模型进行检验并和PR方程（vdw-2混合规则）计算结果进行比较，本模型的平均绝对误差为11.7％，而PR方程的结果为14.9％，对极性溶剂体系的计算结果有显著改善.用此模型直接推算的萘-Co_2体系萘的偏摩尔焓和文献数据相吻合     

Determination and correlation of temperature and pH value dependent solubility of dl-methionine

In order to provide basic data for the crystallization of dl -methionine and understand the thermodynamic properties of dissolution, the solubility of dl -methionine in water was measured by gravimetric method from 294.05 to 347.05 K and the solubility at different pH values under temperature 302.95 to 342.05 K was determined by elemental analysis in this work. The experimental data show that the solubility of dl -methionine increases with increasing temperature as well as more acidic or basic pH values. The van't Hoff equation, modified Apelblat equation, λh equation, Wilson model, NRTL model, and UNIQUAC model were used to correlate the solubility data versus temperature. The melting temperature, enthalpy of fusion, enthalpy and entropy of dissolution were estimated from solubility data and it shows that the expression of solubility by enthalpy and entropy of dissolution gives more reasonable estimation and Wilson model gives a better correlation for these thermodynamic properties.     

Enthalpies of Chromium Oxide Solution in Soda Lime Borosilicate Glass Systems

Chromium oxide (Cr₂O₃) solubility was measured in soda lime borosilicate glass from 1400 to 1500 K. The temperature dependence of the solubility increased with increased sodium oxide concentration. The enthalpies of solution for the equilibrium phases were calculated from the solubility data in the temperature range from 1400 to 1500 K. The enthalpy of fusion for Cr₂O₃ at 1450 K was calculated to be 108.0 kJ·mol⁻¹. This value was less than our measured values for enthalpy of solution, 111.0 ± 0.5 and 158.4 ± 0.3 kJ·mol⁻¹, indicating that all enthalpies of mixing were positive; that is, the mixing process was endothermic. This characterized the interaction between solute and solvent as repulsive.     

Solubility of triclocarban in pure alkanols at different temperatures

Triclocarban solubility in six pure alcohols was determined in the temperature interval from 278.15 to 318.15 K. The experimental solubility data were correlated by the Wilson, the nonrandom two liquid (NRTL) and the universal quasi-chemical (UNIQUAC) models. The data are well fitted with all three models for the six pure alcohols studied here. Also, ab initio geometry optimization of triclocarban was performed using the density functional theory (DFT) based on DMol³ method.