Studies Of Solid-liquid Equilibrium Of Four Pyridine Derivatives

In this thesis, the solid-liquid equilibrium of four kinds of pyridine derivatives -2-aminopyridine, 3-aminopyridine, 2,6-pyridine dichloride and cetylpyridinium bromide in some single solvents and some component solvents were researched.Solvent dissolving, crystallizing and separating was an effective way to separate mixed solids. Exact and intact solubility data were needed in this method. But the bottleneck problem of solubility being determined was terminal determination of dissolution process. We used an equipment of new laser monitoring dynamitic method by computer on line. This equipment determined the equilibrium point exactly and quickly, not only improved the solubility accuracy, but also saved labor and time and improved work efficiency.In this article, the solubilities of 2-aminopyridine in ethanol, acetone, chloroform, ethyl acetate, butyl acetate and ethanol-butyl acetate; 3-aminopyridine in benzene, ethanol, acetone, chloroform, butyl acetate, alcohol-benzene and butyl acetate-acetone; 2,6- pyridine dichloride in benzene, ethyl alcohol, acetic acid, acetone, chloroform, ethyl acetate, ethanol-chloroform and in acetic acid-benzene; cetylpyridinium bromide in methanol, ethanol, acetone, chloroform, glycol, methanol-butyl acetate and ethanol-ethyl acetate were measured systemically in certain temperature range at atmospheric pressure.The experimental data were correlated by the two parameter, three parameter equation andλh equation. The average relative error of 705 data points was 1.73%, 1.11% ,2.73% respectively. Results indicated that all the equation are very well in correlating the experimental data. At last, it was worked out the solution heat of all the systems by the two parameter equation and the three parameter equation.