New methodology for simultaneous volumetric and calorimetric measurements: Direct determination of αp and Cp for liquids under pressure

Lidia Casas (1) , Frédéric Plantier (2) , David Bessieres

1 Departamento de Física Aplicada
2 TEFC - Thermodynamique et Energétique des fluides complexes

A new batch cell has been developed to measure simultaneously both isobaric thermal expansion and isobaric heat capacity from calorimetric measurements. The isobaric thermal expansion is directly proportional to the linear displacement of an inner flexible below and the heat capacity is calculated from the calorimetric signal. The apparatus used was a commercial Setaram C-80 calorimeter and together with this type of vessels can be operated up to 20 MPa and in the temperature range of 303.15-523.15 K, In this work, calibration was carried out using 1-hexanol and subsequently both thermophysical properties were determined for 3-pentanol, 3-ethyl-3-pentanol, and 1-octanol at atmospheric pressure, 5 and 10 MPa, and from 303.15 to 423.15 K in temperature. Finally experimental values were compared with the literature in order to validate this new methodology, which allows a very accurate determination of isobaric thermal expansion and isobaric heat capacity.

Mots clés: 1-hexanol; 1-octanol; 3-Pentanol; Batch cells; Calorimetric measurements; Direct determination; Experimental values; Heat capacities; Isobaric heat capacity; Linear displacements; Temperature range; Thermo-physical property Engineering controlled terms: Atmospheric pressure; Calorimetry; Specific heat; Thermal stress Engineering main heading: Thermal expansion

Domaines: Chimie-Physique [physics.chem-ph]

Lidia Casas, Frédéric Plantier, David Bessieres. New methodology for simultaneous volumetric and calorimetric measurements: Direct determination of αp and Cp for liquids under pressure. Review of Scientific Instruments, 2009, 80 (12), pp.Article number 124902. ⟨10.1063/1.3270258⟩. ⟨hal-00706024⟩