| 摘要 |
PURPOSE:To readily obtain the titled polyhedral crystal salt suitable as table salt, etc., having excellent fluidity, not solidifying, by adding a specific amount of sodium hexametaphosphate to a solution of salt and precipitating crystal by a conventional procedure. CONSTITUTION:A saturated or approximately saturated solution having dissolved purified salt or ordinary salt is put in a container 2 arranged in a temperature controlled water bath 1, 5-1,000ppm sodium hexametaphosphate is added to the solution and agitated by a stirrer 3. Then the solution is sent to a cooler 5 by a pump 4, cooled, the solution of salt made into a supersaturated state is transferred to a crystallizer 6 and seed crystal 7 is added. Crystal is gradually grown around the seed crystal 7, large crystal of octahedron-tetradecahedron is grown, taken out and dried. Instead of crystallizing the crystal by cooling method, the crystal can be crystallized by evaporation concentration method. |
