Sodium hypochlorite low-salt

Commercial Processes. Olin s earlier triple salt process, originally commercialized in 1928, was modified in 1983. In the patented process, a slurry of dibasic calcium hypochlorite is mixed with a strong, low salt sodium hypochlorite solution and hypochlorite Hquors and chlorinated. The resultant Ca(OCl)2 2H20 slurry is filtered, the cake going to the dry-end and the filtrate to the dibasic precipitation step where it reacts with lime. 

FIGURE 24.3 Process diagram for high-strength, low-salt sodium hypochlorite. (Redrawn from Dugua, J., U.S. Patent 4,780,303, 1988.)... 

Low-salt sodium hypochlorite can also be made by chlorinating a slurry of calcium hydroxide. The precipitated calcium hypochlorite compounds are ranoved by filtration and mixed with a solution of sodium hydroxide. The solids are removed by filtration. The resulting solution contains -15% sodium hypochlorite and 1.3% sodium chloride. ... 

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