首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
In this paper, the solubility of 4-nitroimidazole in twelve pure solvents (toluene, benzene, 1,4-dioxane, acetonitrile, ethyl acetate, acetone, GBL, ethanol, methanol, n-butanol, DMF and NMP) were determined by using the laser monitoring system from 278.15 K to 323.15 K under 101.1 kPa, which are 0.00018-0.00070, 0.00021-0.00073, 0.00034-0.00092, 0.00038-0.00142, 0.00047-0.00120, 0.00126-0.00303, 0.00225-0.00517, 0.00310-0.00724, 0.00467-0.00982, 0.00453-0.01940, 0.01947-0.04652, and 0.04670-0.07452, respectively. At constant temperature, the mole fraction solubility of 4-nitroimidazole were increased as the following order: toluene < benzene < 1,4-dioxane < (ethyl acetate or acetonitrile) < acetone < GBL < ethanol < (methanol or nbutanol) < DMF < NMP, and the solubility of 4-nitroimidazole in (ethyl acetate, acetonitrile) and (methanol, n-butanol) had an intersection point at 297.55 K and 281.85 K, respectively. The solubility of 4-nitroimidazole could be increased with increasing temperature in twelve pure solvents. The ideal model, modified Apelblat equation, polynomial empirical equation, and λh equation were used to correlate the experimental values. The experimental solubility values were employed to calculate the standard dissolution enthalpy, standard dissolution entropy and Gibbs energy. The dissolution of 4-nitroimidazole could be an endothermic process in twelve pure solvents. The determination and fitting solubility of 4-nitroimidazole have important guiding significance for the purification and crystallization of its preparation process.  相似文献   

2.
The thermodynamic properties of metamizol monohydrate in pure solvents (methanol,ethanol,n-propanol and isopropanol) and two binary mixed solvent systems including (methanol + ethanol) and (methanol +isopropanol) were measured from 283.15 K to 313.15 K by gravimetric method under atmospheric pressure thought as 0.1 MPa.The modified Apelblat equation,the CNIBS/R-K equation,the Hybrid model and the NRTL model were used to correlate the solubility of metamizol monohydrate,respectively.The results show that the solubility of metamizol monohydrate in all the tested solvents increases with the rising temperature which means that it has temperature dependence.What's more,the effects of solvent components of the binary solvent mixtures on solubility were discussed,it illustrates that the increasing of the molar fraction of methanol gives the system a greater dissolving power.Furthermore,according to the NRTL model,the enthalpy,the Gibbs energy and the entropy of the mixing process were also obtained and discussed.  相似文献   

3.
In this paper, the solubility of 4-nitroimidazole in twelve pure solvents (toluene, benzene, 1,4-dioxane, acetonitrile, ethyl acetate, acetone, GBL, ethanol, methanol, n-butanol, DMF and NMP) were determined by using the laser monitoring system from 278.15 K to 323.15 K under 101.1 kPa, which are 0.00018–0.00070, 0.00021–0.00073, 0.00034–0.00092, 0.00038–0.00142, 0.00047–0.00120, 0.00126–0.00303, 0.00225–0.00517, 0.00310–0.00724, 0.00467–0.00982, 0.00453–0.01940, 0.01947–0.04652, and 0.04670–0.07452, respectively. At constant temperature, the mole fraction solubility of 4-nitroimidazole were increased as the following order: toluene < benzene < 1,4-dioxane < (ethyl acetate or acetonitrile) < acetone < GBL < ethanol < (methanol or n-butanol) < DMF < NMP, and the solubility of 4-nitroimidazole in (ethyl acetate, acetonitrile) and (methanol, n-butanol) had an intersection point at 297.55 K and 281.85 K, respectively. The solubility of 4-nitroimidazole could be increased with increasing temperature in twelve pure solvents. The ideal model, modified Apelblat equation, polynomial empirical equation, and λh equation were used to correlate the experimental values. The experimental solubility values were employed to calculate the standard dissolution enthalpy, standard dissolution entropy and Gibbs energy. The dissolution of 4-nitroimidazole could be an endothermic process in twelve pure solvents. The determination and fitting solubility of 4-nitroimidazole have important guiding significance for the purification and crystallization of its preparation process.  相似文献   

4.
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.  相似文献   

5.
采用动态平衡法,在293.15~332.80 K、常压下,测定了双季戊四醇(DPE)在水+(甲醇、乙醇、异丙醇)三种混合溶剂中的溶解度数据。结果表明:DPE在不同质量分数的水+(甲醇、乙醇、异丙醇)混合溶剂中的溶解度随体系温度升高而增大;同一温度下,其在所选取溶剂体系中的溶解度随着甲醇、乙醇或异丙醇质量分数的增大而先增大后减小。λh方程、两参数方程与Apelblat方程均能够对所测定的溶解度数据进行较好的关联;通过修正的van’t Hoff方程计算得到DPE在所选取溶剂体系中Δsol H 0、Δsol S 0和Δsol G 0均大于零,表明DPE在所选取溶剂体系中的溶解过程为吸热、熵增的非自发过程。  相似文献   

6.
The solubilities of trimethylolethane in butanol,methyl acetate,ethyl acetate as well as in mixed solvents of (methanol + ethyl acetate) and (ethanol + ethyl acetate) were measured with the gravimetTic method in the temperature range from 283.15 K to 318.15 K under atmosphere pressure.The experiment results showed that the solubility of trimethylolethane increased with the temperature,or along with the concentration of methanol or ethanol in the solvents of (methanol + ethyl acetate) and (ethanol + ethyl acetate).In addition,the experiment values were correlated by the van't Hoffequation,Modified Apelblat Equation,λh Equation,CNIBS/R-K equation and Jouyban-Acree Model.The Modified Apelblat Equation provided the best fitting results of the solubility data of TME in the pure solvents while the CNIBS/R-K model showed the best estimation of the solubility in the binary solvent mixtures.Furthermore,the density functional theory (DFT) calculations showed that solubility in different solvents related to the strength of the interaction between the trimethylolethane and the solvent molecules.Finally,the standard molar enthalpy and molar entropy of trimethylolethane during the dissolving process was also calculated by Modified Apelblat equation in this work.  相似文献   

7.
2,4(5)-Dinitroimidazole (2,4(5)-DNI) is an important energetic material, and it is also an important precursor for the preparation of drugs and energetic materials. In this study, the solubility of 2,4(5)-DNI in eleven pure solvents (chlorobenzene, benzene, 1,2-dichloroethane, toluene, water, isopropyl alcohol, ethyl acetate, acetonitrile, methanol, 1,4-dioxane and acetone) were measured by using a dynamic test method from 278.15?K to 323.15?K under 101.1?kPa. Four solubility models were used to fit the experimental data, which were ideal model, modified Apelblat equation, polynomial empirical equation, and λh equation. Meanwhile, the relative average deviation and root-mean-square deviation between the experimental data and the fitted data were also calculated. Furthermore, the three thermodynamic parameters, i.e., dissolution enthalpy, dissolution entropy and Gibbs energy were obtained based on solubility data. Finally, the crude product of 2,4(5)-DNI was crystallized with acetone as solvent, and the purity of the crystalline product was greater than 99.5%.  相似文献   

8.
The solubilities of 3,4‐diaminofurazan (DAF) and 3,3′‐diamino‐4,4′‐azoxyfurazan (DAAF) were investigated in water, dichloromethane, acetonitrile, ethyl acetate, methanol, and acetone between 293.15 K and 313.15 K. The solubility was determined by high‐pressure liquid chromatography with ultraviolet detection. The solubilities of DAF and DAAF are increased with the increasing of temperature in all solvents studied. The enthalpy of solution in each solvent was calculated according to van't Hoff Equation.  相似文献   

9.
The solubility of xylitol in ethanol+water solvent mixtures was measured at temperatures ranging from 278.00 K to 323.00 K at atmospheric pressure by using a laser technique. The results of these measurements were correlated by the combined nearly ideal binary solvent CNIBS/Redlich-Kister equation. The experimental solubility and correlation equation in this work can be used as essential data and models in the purification process of xylitol. The variant 2 in the CNIBS/R-K models was confirmed to be more adaptable to predict solubility of xylitol in binary ethanol +water system. Using the experimentally measured solubilities, the thermodynamic properties of dissolution of xylitol, such as Gibbs energy, molar enthalpy of dissolution, and molar entropy of dissolution, were calculated.  相似文献   

10.
Omeprazole sodium(OMS), a typical non-hydrogen bond donors API, is only available in solvates so far, including monohydrate, ethanol solvate and methanol solvate. The methanol solvate was found for the first time. Solvate transformation thermodynamics of OMS was studied in this paper. First, the ternary phase diagrams forming two solvates for OMS in binary solvent mixtures including methanol + water, ethanol + water, and methanol+ ethanol were measured at temperature ranging of T =(278.15 to 313.15) K under atmospheric pressure. Further, the standard equilibrium constants of the solvate transformation reactions were evaluated according to the chemical reaction isothermal equation. The standard molar Gibbs free energy, the standard molar enthalpy, and the standard molar entropy of solvate transformation reactions were then calculated based on van't Hoff equation. Moreover, the thermodynamic stability of the OMS solvate was analyzed based on phase diagram. The results are of great importance to develop a crystallization process for manufacturing OMS solvate, and could be helpful to other solvate transformation research.  相似文献   

11.
The knowledge of solubility of a salt in either the pure solvent or blend solvent is of great importance for studying or operating the crystallization, extraction, and distillation processes. The solubility of sodium acetate (NaAc) in four pure solvents (water, ethanol, acetic acid and 2,2,2-trifluoroethanol) and four binary solvents (water–ethanol, water-acetic acid, acetic acid–ethanol, and acetic acid-ethyl acetate) were measured by using the laser dynamic method at temperatures from 288.15 K to 338.15 K at 0.1 MPa. The results showed that the solubility of NaAc was influenced by either the solution temperature or solvent composition. The aqueous sodium acetate solution possessed the maximal solubility under the experimental conditions. The solubility of NaAc in 2,2,2-trifluoroethanol was found to be decreased with the increase of the solution temperature. While, the solubilities of NaAc in other seven solvents increased as the solution temperature was elevated. Besides, five correlation models, including the van't Hoff model, modified Apelblat model, Yaws model, λh model, and modified Apelblat-Jouyban-Acree model were used to correlate the solubility data of those sodium acetate solutions with acceptable deviation, respectively. Finally, van't Hoff analysis method was selected to analyze the change law of thermodynamic properties of a salt during the dissolution process.  相似文献   

12.
采用高效液相色谱法测定了常压下在293.15~323.15 K温度范围内反式-4-羟基环己基地氯雷他定在水、质量分数为10% 的甲醇-水、质量分数为20% 的甲醇-水、质量分数为10% 的乙醇-水和质量分数为20% 的乙醇-水中的溶解度,并采用Apelblat方程和λh方程对所得到的溶解度数据进行关联拟合,通过van't Hoff方程计算了其在不同溶剂中的溶解焓和溶解熵。发现反式-4-羟基环己基地氯雷他定的溶解度随着温度的升高和溶剂极性的降低而升高,其溶解过程在实验温度范围内,在所选溶剂中均为吸热熵增过程。  相似文献   

13.
Solubility data were measured for N-chloro succinimide in pure n-butanol, ethyl acetate, acetone, isopropanol, tetrahydrofuran, acetonitrile and acetic anhydride at the temperature range between 278.15 K and 333.15 K under atmospheric pressure by gravimetric method. The solubility of N-chloro succinimide in those selected solvents increased with increasing temperature. The solubility data were correlated with the modified Apelblat equation and the van??t Hoff equation to obtain the model parameters. The experimental results could be useful for optimizing the process of purification of N-chloro succinimide in industry. Isopropanol could be the excellent solvent in the crystallization of N-chloro succinimide.  相似文献   

14.
在283.15~323.25 K范围内,利用在线浊度法测定了异烟肼在甲醇、乙醇、正丙醇、异丙醇、正丁醇、异丁醇、丙酮、乙腈、乙酸甲酯与乙酸丁酯中的溶解度。数据表明,异烟肼在不同溶剂中的溶解度均随着温度升高而增加。在同一温度下,异烟肼的溶解度与溶剂关系符合如下顺序:甲醇 > 丙酮 > 乙醇 > 正丙醇 > 异丙醇 > 乙酸甲酯 > 异丁醇 > 正丁醇 > 乙腈 > 乙酸丁酯。采用改进的Apelblat、Wilson与NRTL方程对溶解度数据进行了拟合,结果与实验数据有较高的吻合。基于溶解度数据,对异烟肼溶解焓、溶解熵与溶解吉布斯能进行了计算,发现异烟肼溶解过程是吸热熵增过程。分析了甲醇、乙醇、正丙醇与丙酮对异烟肼冷却结晶过程所获产品晶习的影响,确定乙醇为合适的结晶溶剂。  相似文献   

15.
The solubility of nonivamide in dimethyl sulfoxide, methanol, acetone, ethyl acetate, methyl tert-butyl ether, ace-tonitrile, n-hexane and water over the temperature range of 293.2 K to 323.2 K was mea...  相似文献   

16.
L-arabinose and D-galactose could be released during the hydrolysis process of Arabic gum. The development of a crystallization process of L-arabinose is highly dependent on the knowledge of the solubility of both saccharides. In this work, the solubility of L-arabinose and D-galactose in binary mixtures of methanol-water or ethanol-water (mole fraction of water ≤0.5816) was determined at temperatures between 278.15 and 333.15 K by a static equilibrium method. The experimental data correlated well with the modified Apelblat equation, the simplified polynomial empirical equation, NRTL model and UNIQUAC model. Additionally, the thermodynamic properties including the dissolution enthalpy and entropy were obtained from the experimental data. Within the studied temperature range, the dissolution is endothermic and the dissolution process is non-spontaneous.  相似文献   

17.
Vapor pressures were measured for six binary systems containing water, ethanol, or methanol with one of the two ionic liquids (ILs) at different component concentrations and temperatures using a quasi-static ebulliometer, with the ILs mono-ethanolammonium formate ([HMEA][HCOO]) and di-ethanolammonium formate ([HDEA][HCOO]). The vapor pressures of the IL-containing binary systems are well correlated using the NRTL model with an overall average absolute relative deviation (AARD) of 0.0062. The effect of ILs on the vapor pressure depression of sol-vents at 0.050 mole fraction of IL is that [HDEA][HCOO]〉[HMEA][HCOO], and the vapor pressure lowering de-gree follows the order of water〉methanol〉ethanol. Further, the activity coefficients of three solvents (viz. water, ethanol, and methanol) for the binary systems{solvent (1)+IL (2)}predicted based on the fitted NRTL parameters at T=333.15 K indicate that the two ILs generate a negative deviation from Raoult’s law for water and methanol and a positive deviation for ethanol to a varying degree, change the relative volatility of a solvent. [HMEA][HCOO] may be a promising entrainer to efficiently separate ethanol aqueous solutions by special rectification.  相似文献   

18.
Solid-liquid equilibrium data of cefquinome sulfate is important to develop industrial crystallization processes for cefquinome sulfate. The solubilities of cefquinome sulfate in five pure solvents (methanol, ethanol, ethylene glycol, acetic acid and water) from 277.15 to 305.15 K and in a binary acetone-water solvent from 278.15 to 293.15 K were measured at atmospheric pressure. The pure-solvent solubility data was correlated to the modified Apelblat and Van’t Hoff equations whereas the mixed-solvent system data was correlated to the modified Apelblat, Van’t Hoff, CNIBS/R-K and Jouyban- Acree models. It was found that the solubilities of cefquinome sulfate in all tested solvents decreased with the increasing of temperature. In addition, the thermodynamic properties of the dissolution processes, including standard Gibbs free energy, enthalpy and entropy changes, were calculated using the Van’t Hoff equation. It was found that the dissolution of cefquinome sulfate is exothermic.
  相似文献   

19.
The selective solvation of silver(I) bromate in the binary solvent mixtures of methanol + acetonitrile and ethanol + acetonitrile has been studied at 30°C by solubility and emf measurements. The solubility of the salt increases with the addition of acetonitrile up to a mole fraction (XAN) of 0.6 and 0.7 in the case of methanol + acetonitrile and ethanol + acetonitrile respectively and then decreases with further addition of the same. The transfer free energy of the silver ion (molal scale) decreases continuously with the addition of acetonitrile in both the mixtures. The transfer free energies of bromate ion (molal scale) are found to be quite small up to XAN ≈ 0.7 in both methanol + acetonitrile and ethanol + acetonitrile mixtures and then increase. The solvent transport number Δ, of acetonitrile is positive with a maximum at XAN = 0.55 (Δ = 2.7) and at XAN = 0.45 (Δ = 2.2) for methanol + acetonitrile and ethanol + acetonitrile systems respectively. These results have been interpreted as arising due to a heteroselective solvation of the salt with the silver ion being preferentially solvated by acetonitrile and the bromate ion by the amphiprotic component which is marked especially at higher compositions.  相似文献   

20.
The solubility of meropenem trihydrate in water + acetone mixtures and water + tetrahydrofuran mixtures were determined from T =(278.15 to 303.15) K by static method under atmospheric pressure.Effects of solvent composition and temperature on solubility of meropenem trihydrate were discussed.To extend the applicability of the solubility data,experimental solubility data in two kinds of binary solvent mixtures were correlated by the Apelblat equation and NIBS/Redlich-Kister model.It was found that the two models could satisfactorily correlate the experimental data and the Apelblat equation could give better correlation results.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号