Studies on Salt Hydrates for Latent Heat Storge. VI. Preheating Effect on Crystallization of Sodium Acetate Trihydrate from Aqueous Solution with a Small Amount of Disodium Hydrogenphosphate

With particular reference to the use of Na2HPO4 as nucleation catalyst for crystallization of CH3CO2Na·3H2O, influences of preheating temperature and time were studied on the crystallization of CH3CO2Na·3H2O from three kinds of CH3CO2Na aqueous solutions, whose concentrations were 58.0, 60.3, and 62.8 wt%. In 60.3 wt% aqueous solution (CH3CO2Na·3H2O), the nucleation catalyst begins to get deactivated by preheating at 81 °C. The temperature at which the catalyst begins to get deactivated is slightly raised with increasing CH3CO2Na concentration of the solution. The results obtained are compared with those previously reported on the use of Na4P2O7·10H2O as nucleation catalyst, and are discussed on the basis of the crystalline adsorption model.