WO 2021/120705 A1

Method for preparing α-hemihydrate

(22) 07.09.2020

(43) 24.06.2021

(57) Disclosed is a method for preparing α-hemihydrate gypsum, the method involving using citric acid as a crystal transformation agent to prepare dihydrate gypsum, and then subjecting the dihydrate gypsum to crystal transformation under the excitation effect of an α-hemihydrate gypsum seed to prepare α50 grade α -hemihydrate gypsum meeting the standard specification of JC/T 2038-2010.

(71) Jiangsu Efful Science and Technology Co., Ltd, Jiangsu 211178 (CN)


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