Vapor pressure measurements of tobacco pyrolysis tar by a non-isothermal Knudsen effusion method

Abstract

Vapor pressures of thermal decomposition products of tobacco were measured using a molecular effusion/thermogravimetric technique based on a non-isothermal Knudsen effusion method. Molecular weight distributions of the tobacco tar and its fractions were obtained by Field Ionization Mass Spectroscopy. The preliminary tobacco tar study showed that the heat of vaporization and boiling point at 760 Torr of the initial 24% mass loss fraction were about 129 kJ mol −1 and 568 K, respectively. In the case of the hexane phase partitioned tar, the heat of vaporization and boiling point at 760 Torr of the initial 15% mass loss fraction were about 118 kJ mol −1 and 544 K, respectively.