| 摘要 |
Solid calcium hypochlorite is obtained from solutions thereof having a low concentration of calcium chloride without appreciable loss of available chlorine by imparting to the solution a slight but permanent alkaline reaction by addition or formation of calcium hydroxide, and rapidly evaporating the solution to dryness in a finely divided condition in hot air at atmospheric pressure, as by atomizing or spraying the solution. A caustic soda solution may be used to produce the calcium hydroxide, and the dry product may be further dehydrated to produce anhydrous crystals, if necessary in vacuo. Previously concentrated hypochlorite liquors may be used in the process and inert gases, for instance nitrogen, may replace the hot air. In an example air at a temperature of 130-140 DEG C. is used, giving a drying temperature of 70-80 DEG C.
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