Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Thermophysical property measurements on tetrabutylphosphonium sulfate ionic semiclathrate hydrate consisting of the bivalent anion

Arai, Y.[Yuta], Koyama, R.[Ryo], Endo, F.[Fuyuaki], Hotta, A.[Atsushi], Ohmura, R.[Ryo]
J. Chem. Thermodyn. 2019, 131, 330-335
ABSTRACT
To develop the hydrate thermal energy storage technology , it is desired to reveal the mechanism of the thermophysical property manifestation on ionic semiclathrate hydrate. The influence of valence on thermophysical properties has not been investigated so far. In the present study, the phase equilibrium temperatures and the dissociation heats of tetrabutylphosphonium sulfate ((TBP)2SO4) ionic semiclathrate hydrate were experimentally studied. (TBP)2SO4 hydrate consists of the bivalent anion, SO4 2 . The highest phase equilibrium temperature was 6.5 C at the mass fraction range from 0.363 to 0.384. The largest dissociation heat was (168.8 +- 2.4) kJ kg 1 at the mass fraction 0.374. These values of the phase equilibrium temperature and the dissociation heat were respectively lower and smaller than those of the ionic semiclathrate hydrates with the monovalent anion. As a new choice for thermal energy storage medium, (TBP)2SO4 hydrate would be suitable to the automotive air conditioner and the cold chain for blood or perishable foods.
Compounds
# Formula Name
1 H2O water
2 C32H72O4P2S tetrabutylphosphonium sulfate
Datasets
The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type Compound-# Property Variable Constraint Phase Method #Points
  • POMD
  • 1
  • 2
  • Solid-liquid equilibrium temperature, K ; Liquid
  • Mass fraction - 2; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • Crystal of intercomponent compound 1
  • VISOBS
  • 10