The reaction of MgCl2·4H2O with CCl2F2

A new reaction of MgCl2·4H2O with CCl2F2 is investigated by DTA and TG from room temperature to 350 °C. It is observed that MgF2 was obtained between 252 and 350 °C, Below the temperature, MgCl2·4H2O dehydrates and hydrolyzes to MgCl2 and Mg(OH)Cl, which are the real reactants of the reaction with CCl2F2. The formation of MgF2 is ascribed to the reaction of MgCl2 and Mg(OH)Cl with HF, which forms by decomposition of CCl2F2 with the taking part in of H2O released from dehydration of hydrated magnesium chloride on the surface of MgCl2 and Mg(OH)Cl, which catalyzes the decomposition of CCl2F2 in this case. Consequently, the reactions are tested in the fluid-bed condition. It is found that MgF2 formed at temperatures down to 200 °C in a fluid-bed reactor. This reaction may be used as a method of disposing of the environmentally sensitive CCl2F2 (rather than release into the atmosphere). It is also a method for the preparation of MgF2.