Determination of the Vapor Pressure-Temperature Relationship of the Drug Metronidazole Using Thermogravimetry

摘要

Metronidazole evaporates when subjected to thermogravimetry in a nitrogenrnatmosphere. The process is zero order and plots of ln k versus reciprocal temperature (K)rngive a value of 85.72 kJ mol~(-1) for the activation energy. On the basis that equilibrium isrnachieved at all temperatures, the data is used to establish a plot of the vapor pressurerncurve versus temperature. This method requires that the equipment be calibrated and datarnfor benzoic acid used for this purpose.