摘要 |
<p>Neutral Ca hypochlorite is prepd. by (a) forming dibasic Ca hypochlorite by adding lime to recycled mother liquor from step. (f), (b) simultaneously chlorinating caustic soda and the dibasic Ca hydrochlorite from (a) in the presence of preformed crystals of sodium chloride and neutral calcium hypochlorite, (c) sepg. the neutral Ca hypochlorite from the sodium chloride by flotation, (d) sepg. the NaCl from the mother liquor from (c), (e) washing the NaCl with the dibasic Ca hypochlorite mother liquor, (f) filtering the suspensions of sodium chloride and neutral calcium hypochlorite, and (g) recycling the mother liquors to steps (b) and (a), respectively. Gives neutral calcium hypochlorite having a high content of active chlorides all of the mother liquors are recycled, thus avoiding pollution problems. Total recovery of solid components is effected.</p> |