Form-Stabilized Eutectoid Salt Hydrate Phase Change Materials That Store and Release Thermal Energy Between 8 Degrees C and 16 Degrees C

Abstract

Eutectoid salt hydrate phase change material compositions for thermal energy storage are disclosed. A congruently melting, form-stabilized, homogenous salt hydrate phase change material includes both attapulgite clay and sodium polyacrylate, where the attapulgite clay functions as both a thixotropic dispersant during the mixing of the salt hydrate, and thereafter in concert with sodium polyacrylate in forming a permanent stabilizing matrix. In addition, in one preferred embodiment, a eutectoid salt hydrate is disclosed which changes phase between 11 degrees C. and 16 degrees C. and whose composition is one mol sodium sulfate decahydrate to 0.5 mols ammonium chloride to 0.22 moles potassium chloride. In a second preferred embodiment, a eutectoid salt hydrate is disclosed that changes phase between 8 degrees C. and 13 degrees C. and whose composition is one mol sodium sulfate decahydrate to 0.65 mols ammonium chloride to 0.22 mols potassium chloride.

Dependencies are inferred from the claim text.