Measurement and correlation of solid–liquid equilibria for three binaries, ethanol–antipyrine, chloroform–antipyrine, and dimethyl ether–antipyrine

Solid–liquid equilibrium (SLE) was measured for three binaries systems, ethanol–antipyrine, chloroform–antipyrine, and dimethyl ether–antipyrine by use of two apparatus based on a direct temperature measuring method. For dimethyl ether–antipyrine, a high pressure variable volume cell was employed, and the pressure was held constant at 5 MPa. Other measurements were carried out by use of a pressure resistance glass tube at the bubble point pressure. Prior to the measurements, SLE was measured for cyclohexane–naphthalene to ensure the reliability of the method. Comparing the three binary systems containing antipyrine, the molar solubility of antipyrine in chloroform was 1.5 times larger than that in ethanol, and 13.5 times larger than that in dimethyl ether at 313 K. The data were correlated with Schroder-van Laar and NRTL equations under the assumption that the binary system had a simple eutectic temperature. The data could be correlated within 0.168%, 0.775%, and 0.102% in temperature for the ethanol–antipyrine, chloroform–antipyrine, and dimethyl ether–antipyrine binary systems, respectively.