| 摘要 |
A continuous cyclic process for production of calcium hypochlorite wherein an aqueous solution saturated with calcium hypochlorite and sodium chloride is chlorinated by using chlorine gas to produce sodium chloride crystals and an aqueous chlorinated reaction mixture, the formed sodium chloride crystals being then separated from said aqueous chlorinated reaction mixture. First sodium hydroxide is added to the foregoing aqueous solution which solution also contains calcium hypochlorite and sodium chloride in the crystal phase. Then calcium hydroxide and sodium hydroxide is further added to the aqueous chlorinated reaction mixture remaining after separation of said crystals therefrom. This mixture containing calcium hydroxide and sodium hydroxide is again chlorinated with chlorine gas to produce a slurry containing mainly sodium chloride crystals, calcium hypochlorite crystals and a mother liquor saturated with calcium hypochlorite and sodium chloride. The obtained slurry is divided into a first slurry [I] having mainly calcium hypochlorite crystals, sodium chloride crystals and mother liquor saturated with calcium hypochlorite and sodium chloride, and a second slurry [II] containing calcium hypochlorite crystals with a small amount of sodium chloride crystals and mother liquor saturated with calcium hypochlorite and sodium chloride. The second slurry [II] is then treated so as to remove the calcium hypochlorite crystals with a small amount of sodium chloride crystals thus forming a third phase mother liquor [III] saturated with calcium hypochlorite and sodium chloride. This third phase mother liquor [III] and the first slurry [I] is then recycled to the first step, i.e., the aforesaid aqueous solution with saturated calcium hypochlorite and sodium chloride containing a small amount of calcium hypochlorite crystals and sodium chloride crystals. |
