Evaluation of Phenylnaphthalenes as Heat Transfer Fluids for High Temperature Energy Applications

Abstract

The thermodynamic properties of 1- and 2-phenyl substituted polyaromatic hydrocarbons have been measured and estimated under conditions relevant to heat transport applications almost to the critical point. Densities, vapor pressures, and heat capacity measurements were used to derive critical temperature, pressure, and density for the phenylnaphthalenes. The thermal and radiolytic stability of 1-phenylnaphthalene was examined using thermogravimetric analysis, differential scanning calorimetery, and gamma irradiation. Low melting point, low vapor pressure, high critical temperature, and resistance to thermal decomposition may make phenylnaphthalenes suitable for heat transfer applications up to 800 K, including power generation and separations processes.

Keywords:

• concentrating solar power energy storage
• high temperature heat transfer fluids
• substituted naphthalenes
• thermodynamic properties

ACKNOWLEDGEMENTS

This research was sponsored by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory (ORNL), managed by UT-Battelle, LLC for the U.S. Department of Energy under contract DE-AC05-00OR22725.

This submission was sponsored by a contractor of the United States Government under contract DE-AC05-00OR22725 with the United States Department of Energy. The United States Government retains, and the publisher, by accepting this submission for publication, acknowledges that the United States Government retains, a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this submission, or allow others to do so, for United States Government purposes.

Notes

^a From fit of experimental density data to get critical point.

^b From Riedel equation calculation using calculated critical temperature and acentric factor, and reference density at 396 K.