Vapor pressure data for fatty acids obtained using an adaptation of the DSC technique

The vapor pressure data for lauric (C12:0), myristic (C14:0), palmitic (C16:0), stearic (C18:0) and oleic (C18:1) acids were obtained using Differential Scanning Calorimetry (DSC). The adjustments made in the experimental procedure included the use of a small sphere (tungsten carbide) placed over the pinhole of the crucible (diameter of 0.8 mm), making it possible to use a faster heating rate than that of the standard method and reducing the experimental time. The measurements were made in the pressure range from 1333 to 9333 Pa, using small sample quantities of fatty acids (3–5 mg) at a heating rate of 25 K min−1. The results showed the effectiveness of the technique under study, as evidenced by the low temperature deviations in relation to the data reported in the literature. The Antoine constants were fitted to the experimental data whose values are shown in Table 5.

► Vapor pressure data of fatty acids were measured by Differential Scanning Calorimetry.
► The DSC technique is especially advantageous for expensive chemicals.
► High heating rate was used for measuring the vapor pressure data.
► Antoine constants were obtained for the selected fatty acids.