Modification ofthe High-Pressure Cell in the Hildebrand’sDevice to Determine the Thermal Pressure Coefficients of Liquids:Search for Correlations between Thermal Pressure Coefficients andVarious Physicochemical Parameters

In this work, we have modified the high-pressure cell in the Hildebrand’s device for the determination of the thermal pressure coefficients of liquids. Instead of a glass cell of constant volume, we propose to use a metal cell. As a container of constant volume, a custom cell of corrosion-resistant steel with a pressure range of up to 60 MPa was used. Such significant maximum pressure also enables the temperature range to be increased for the reliable determination of the thermal pressure coefficients. Using the metal cell in the Hildebrand’s device, the thermal pressure coefficients of 14 organic liquids have been determined. The deviations between the obtained results and the literature data were within the measurement errors. We have found that the thermal pressure coefficient of simple organic liquids correlates with their packing coefficients.