Studies On The Excess Properties Of Binary Systems Of Diketones And Alcohols

The interactions between molecules in non-electrolyte solutions are more complicated than that in pure components. The overall thermodynamics properties of mixing components in solutions are not simply equal to the addition of the properties of each component before mixing. The excess molar enthalpies reflect the heat deviation of the condition of actual solution from that of the ideal solution. For excess molar volumes, they reflect the deviation in volume between the actual solution and the idea one. The measurement of excess properties is helpful for us to better understand the micro-structure of solution and interaction of molecules, to provide experimental basis for construction and perfection of theoretical models, and to offer basic thermodynamics data for industrial production.In the first chapter of this dissertation, the applications of calorimeter, activity coefficient models in solution thermodynamics, the measurement methods of excess molar volumes, and the trend of excess property studies are described, basing on which we continue our discussion in the latter part of this dissertation.In the second chapter, we have measured several binary systems containing diethyl malonate, diethyl oxalate and alcohols, alkane, and small ester at p= 101.3 kPa and a series of temperatures by CSC4400 flow mixing microcalorimeter. We analyzed the phenomenon from the aspects of interactions between molecules, fitted the experimental data by Redlich-Kister equation, NRTL and UNIQUAC models, discussed the effect of temperature to parameters, and compared the models used in fitting process.In the third chapter, the densities of binary systems of diethyl malonate, diethyl oxalate with alcohols were measured by an oscillating densimeter at ordinary pressure and a series of temperatures. Based on these densities, we calculated the molar excess volumes of the binary systems. The relation between excess molar volumes and temperature, structure of molecules are discussed, and experimental data were correlated by Redlich-Kister equation.In the last chapter, we summarized the work of this dissertation and illustrated the insufficiencies of our work that are suggestive for the further study.