| 摘要 |
PURPOSE:To remove sulfate ions from an aqueous solution of alkali metal chloride (salt water) containing sulfate ions by bringing zirconium hydroxide into contact with the salt water in a slurry state under acid condition, adsorbing the sulfate ions and then separating the zirconium hydroxide. CONSTITUTION:Zirconium hydroxide is brought into contact with the salt water containing sulfate ions under acid conditions in a slurry state. The sulfate ions in the salt water are adsorbed to zirconium hydroxide by ion exchange reaction. The zirconium hydroxide with adsorbed sulfate ions is separated from the salt water, dispersed in another aqueous solution, allowed to react with alkali to desorb. The zirconium hydroxide used in this method is preferably in a powder state before use, having 50wt.% integrated quantity measured by sedigraph method and 1-20mum particle size. Burning loss of zirconium hydroxide is preferably 3-40wt.%. (After dried at 40 deg.C for 16 hours to remove adsorbed water, zirconium hydroxide is heated at 1000 deg.C for one hour. Zirconium hydrox ide is weighed before and after heating. The burning loss is obtained by calculat ing (weight before burning - weight after burning/weight before burning X100(%)). |
