碱金属溴化物在多种酰胺与水混合溶剂中的相平衡研究

发布时间：2017-12-28 11:34

本文关键词：碱金属溴化物在多种酰胺与水混合溶剂中的相平衡研究　出处：《陕西师范大学》2016年硕士论文　论文类型：学位论文

【摘要】：有机溶剂的加入通常会减小盐在水溶液中的溶解度,以此方式进行盐的分离和纯化,是传统相化学研究的目标。本文是对本课题组工作的延续,选择碱金属溴化物+酰胺+水体系为研究对象,对碱金属溴化物在混合溶剂中的平衡溶解度及饱和溶液密度和折光率的测定,可以为溶液化学提供基础热力学数据,有望将其应用于化学、化工和科研等领域。1.酰胺的选择：从结构和酰胺的性质出发,选择了甲酰胺(FA),N-甲基甲酰胺(NMF), N,N-二甲基甲酰胺(DMF),乙酰胺(MA),N-甲基乙酰胺(NMA), N,N-二甲基乙酰胺(DMA)和N,N-二乙基甲酰胺(DEF)共7种酰胺。2.系统地测定了碱金属溴化物MBr (M=Na, K, Rb, Cs)+酰胺+水三元体系在T=(283.15,298.15,308.15,313.15,318.15)K下的等温溶解度、密度和折光率。在实验温度和全部酰胺与水不同比例范围内,体系均为简单的固-液相平衡。碱金属盐在混合溶剂中的溶解度随着温度的升高而增大,随着混合溶剂中酰胺质量分数的增加而减小；密度的变化与溶解度呈现一致的趋势,而折光率随温度和酰胺质量分数的变化呈现不同的变化趋势。在此基础上,探讨了酰胺结构对体系物化性质的影响。3.对体系的等温溶解度、密度和折光率,使用四参数经验方程进行关联。对等温溶解度还采用了NRTL和UNIQUAC活度系数模型进行了拟合。使用UNIQUAC模型计算了三元体系在实验温度下的平均活度系数4.测定了以上体系在不同组成时的多温溶解度(283.15-318.15 K)。对多温溶解度采用Apelblat方程和λh方程进行了拟合,计算了相关热力学函数,从热力学的角度解释了溶质在混合溶剂中的溶解过程。
[Abstract]:The addition of organic solvent generally reduces the solubility of salt in aqueous solution, this way of salt separation and purification, the objective of the study is the traditional phase chemistry. This paper is a continuation of the work of our research group, choose water system alkali bromide + + amide as the research object, the equilibrium solubility of alkali metal bromides in mixed solvents and determination of saturated solution density and refractive index, can provide the basis of thermodynamic data for solution chemistry, is expected to be applied to Chemistry and chemical engineering and scientific research etc. field. The choice of 1. amide: starting from the properties of structure and amide, we selected formamide (FA), N- methylformamide (NMF), N, N- two, methyl formamide (DMF), acetamide (MA), N- methyl acetamide (NMA), N, N- two methyl acetamide (DMA), and 7 kinds of amides (two). 2. systematically determined the isothermal solubility, density and refractive index of alkali metal bromide MBr (M=Na, K, Rb, Cs) + amide + water three yuan system under T= (283.15298.15308.15313.15318.15) K. In the range of experimental temperature and total amides and water, the system is a simple solid - liquid equilibrium. The solubility of alkali metal salts in mixed solvents increases with the increase of temperature decreases with the increase of the amide content in mixed solvent; the solubility change and density showed a consistent trend, while the refractive index changes with temperature and mass fraction of the amide change trend of different presentation. On this basis, the effect of amide structure on the physicochemical properties of the system was discussed. 3. the isotherm solubility, density and refractive index of the system were correlated by using the four parameter empirical equation. The NRTL and UNIQUAC activity coefficient models were also used to fit the equivalent temperature solubility. The average activity coefficient was calculated using the UNIQUAC model of the three systems in the experimental temperature above 4. determination system in different composition of the multi solubility (283.15-318.15 K). The multi temperature solubility by using Apelblat equation and H equation were fitted, the thermodynamic function calculation, explain the dissolution process of solute in mixed solvents from the point of view of thermodynamics.
【学位授予单位】：陕西师范大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：O642.42

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