An experimental setup for isobaric heat capacities for viscous fluids at high pressure: Squalane, bis(2-ethylhexyl) sebacate and bis(2-ethylhexyl) phthalate

Abstract

A high-pressure flow calorimeter has been used to determine highly accurate isobaric heat capacities for different viscous fluids, squalane (SQN), bis(2-ethylhexyl) sebacate (DEHS) and bis(2-ethylhexyl) phthalate (DEHP) from T=(293.15 to 353.15)K and up to 30MPa. The experimental device was adapted for viscous liquids at high pressure and it can measure heat capacities with an estimated total uncertainty better than 1%. The isobaric heat capacity values were analysed together with their temperature and pressure dependences. In addition, a fitting equation of the experimental molar isobaric heat capacity for these viscous fluids as a function of temperature and pressure was proposed.