STUDIES ON SALT HYDRATES FOR LATENT-HEAT STORAGE .7. THE RELATION BETWEEN ACTIVATION PROCESS OF CRYSTAL NUCLEATION CATALYSTS FOR SODIUM-ACETATE TRIHYDRATE AND THEIR DEACTIVATION TEMPERATURES

Influences of preheating temperature were studied on crystallization of CH//3CO//2Na multiplied by (times) 3H//2O from its melts containing a small amount of Na//4P//2O//7 or Na//2HPO//4 as a crystal nucleation catalyst. The relation between the activation process of these nucleation catalysts and their deactivation temperatures was investigated in detail. Aging of nucleation catalyst which was preceded by forced crystallization of CH//3CO//2Na multiplied by (times) 3H//2O from Na//2HPO//4 was used as a nucleation catalyst, the deactivation temperature was raised by lengthening aging time at a constant aging temperature. When the catalysts were aged for 4 d at 20 degree C, the aging effect on them was almost saturated.