Non-corrosive latent cold storage material based on ethylene glycol - contg. oxide crystallised in rutile system as nucleating agent to minimise supercooling

摘要

Latent cold storage material consists of ethylene glycol (I) as organic storage material and an oxide (II) crystallinised in the rutile system as nucleating agent. Pref. (II) is Sn02, Pb02, Ti02, beta-Mn02 and/or Zr02 esp. Sn02. USE/ADVANTAGE - The material is non-corrosive and available on the technical scale. It has a storage density of 210 mJ/cu.m m.pt. of -14 deg.C and supercooling range of 2-12 K, independently of the kinetics of heat transfer. It is used in refrigeration plant to bridge the delay between cold generation and demand and can be used under static and dynamic conditions. In an example, (I) (0.2% water, max. 0.3% diethylene glycol) was mixed wth 0.005 wt. pts. Sn02 (tetragonal cassiterite structure with ao = bo = 4.72, co = 3.17) and placed in a sealed container. Cold was supplied and removed under static conditions. (I) froze at -18 +- 1 deg.C and melted at -14 deg.C wihtout decomposition. In the range (-) 0 - (-) 20 deg.C. the storage density was 231 MJ/cu.m. (I)