Patent Number: 6,309,621

Title: Process for producing high test hypochlorite and calcium chloride aqueous solution

Abstract: An economical, industrial and ecologically-sound process for producing high test hypochlorite and a calcium chloride aqueous solution comprising the steps of (a) preparing milk of lime, (b) chlorinating the milk of lime to crystallize calcium hypochlorite dihydrate in the presence of the prismatic calcium hypochlorite dihydrate seed crystals having a specific habit to prepare a slurry of coarse calcium hypochlorite dihydrate crystals, (c) separating the slurry into a wet cake of calcium hypochlorite dihydrate crystals and a mother liquor containing calcium hypochlorite and calcium chloride, (d) drying the wet cake to provide high test hypochlorite, and (e) adding hydrochloric acid to the mother liquor or bringing the mother liquor into contact with an oxide of at least one of Mn, Fe, Co, Ni, Cu, and Pd to decompose the calcium hypochlorite to obtain a calcium chloride aqueous solution.

Inventors: Abe; Yoshio (Yamagata, JP), Ohashi; Koichi (Yamagata, JP), Gotoh; Nobuyuki (Yamagata, JP), Murakami; Tsugio (Yamaguchi, JP)

Assignee: Tosoh Corporation

International Classification: C01B 11/00 (20060101); C01F 11/00 (20060101); C01F 11/24 (20060101); C01B 11/06 (20060101); C01B 011/06 (); C01F 011/24 ()

Expiration Date: 10/30/2018