ANHYDROUS MAGNESIUM CHLORIDE

摘要

Anhydrous magnesium chloride is prepared by a process in which hydrated magnesium chloride (10) is mixed in a vessel (11) with ethylene glycol (12). The mixture (13) is dehydrated in distillation columns (14, 15 and 16) with the dehydrated ethylene glycol magnesium chloride solution (20) pumped into a crystalliser (21) simultaneously with the separate addition of anhydrous ammonia gas (22) to the crystalliser (21). Prior to the introduction of reactants (20 and 22), the crystalliser (21) contains ethylene glycol saturated with ammonia. A crystalliser slurry of magnesium chloride hexammoniate (23) is continuously pumped from the crystalliser (21) into a pressure filter (24) where the crystals are washed with methanol saturated with ammonia (26). The washed crystals (27) are transferred to a fluidised bed calciner (28) where methanol is evaporated from the crystals at 120 DEG C and therefter the crystals are calcined to anhydrous magnesium chloride at 450 DEG C.