公开(公告)号：US20230271845A1

公开(公告)日：2023-08-31

申请号：US18014356

申请日：2021-12-24

申请人： Shiraishi Kogyo Kaisha, Ltd.

发明人： Hiromitsu Sakaguchi ,  Sayaka Oguni ,  Kenichiro Eguchi ,  Toru Oda ,  Yasunori Nanri

IPC分类号： C01F11/18 ,  B01D53/14

CPC分类号： C01F11/181 ,  B01D53/1475

摘要： To produce a calcium carbonate in a controlled form while carbon dioxide gas is efficiently used. A method for producing a calcium carbonate comprises a carbon dioxide gas absorption step of allowing an aqueous sodium hydroxide solution at a concentration of 5 to 21% to absorb carbon dioxide gas to give an aqueous sodium carbonate solution at a concentration of 4 to 24%; a hydration step of reacting calcium oxide with an aqueous sodium hydroxide solution at a concentration of 0 to less than 6% to give a lime milk that is a suspension of calcium hydroxide having a BET specific surface area of 5 to 40 m2/g; and a carbonation step of adding the aqueous sodium carbonate solution to the lime milk and performing reaction.