Thermodynamic Studies of Solubility for Naphthalene in 12 Solvents from 279 to 330 K

Abstract

The solubilities of naphthalene in decalin, octane, dodecane, dichloromethane, trichloromethane, carbon tetrachloride, 1,2-dichloroethane, o-dichlorobenzene, 1-octanol, 2-octanone, 4-methyl-2-pentanone, and benzene were measured by a dynamic method over the temperature range of 279 to 330 K at atmospheric pressure. By comparison, the experimental results indicated that the molality solubility in dichloromethane reached maximum at certain temperature. Then, the Apelblat equation, the λh equation, the Wilson equation, and the nonrandom two liquid (NRTL) equation were used to correlate the experimental data. The NRTL equation was regarded as the effective model for all the solvents. Finally, the mixing properties were also calculated based on the NRTL equation. All these data were particularly instructive for the process of recycling naphthalene.

Solubility Determination and Thermodynamic Properties of Bezafibrate in Pure and Binary Mixed Solvents

“…For a solid–liquid phase equilibrium system at fixed temperature and pressure, the solubility of a solute in a solvent can be expressed as eq . , where x i is the mole fraction solubility of the solute; γ i is the activity coefficient of the solute; Δ fus H is the fusion enthalpy of the solute; R is the ideal gas constant with a value of 8.314 J·mol –1 ·K –1 ; T is the temperature; and T m is the melting temperature of the solute. The activity coefficient of the solute, γ i , can be evaluated by Wilson or NRTL models.…”

“…For a solid−liquid phase equilibrium system at fixed temperature and pressure, the solubility of a solute in a solvent can be expressed as eq 3. 14,15 i k j j j j j y…”