摘要 |
CaSO4.2H2O, useful as bean curd coagulant having high purity, solubility and ultra fine particle crystal structure, was manufd. by reacting sulfuric acid with calcium salt soln. which was obtained by reacting CaCO3 with acid. For e.g., excess CaCO3 was put-in 2N-HNO3 500ml for 1-2hrs. to give Ca (NO3)2 soln., wherein 64% H2SO4 46L was put-in and dehydrated to give pure CaSO42H2O 64kg and the filtrated 2N-NHO3 was recorved.
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