反应 #1470437
ord-17793924a853446891743e8f1d084a8c
反应方程式
反应条件
后处理
- 1其他9, 1993 which is forming the technical background of the present invention
- 2其他is provided
- 3workup.WAITthe residence time is 1.0 s to 1.5 s
- 4其他during 10 to 20 min
- 5其他After the feeding of acid is terminated
- 6workup.ADDITIONthe obtained suspension of the product
- 7workup.ADDITIONThe resulting suspension of hydroxylapatite
- 8其他Additionally, the suspension may be dried
实验过程
93012609/26, filed on Mar. 9, 1993 which is forming the technical background of the present invention. According to this method a suspension of calcium hydroxide is reacted with phosphoric acid in a closed multiple circuit whereby the suspension of calcium hydroxide is past through two zones. In the first zone a continuous supply of phosphoric acid in the amount necessary to reach pH=10-11 is provided. The suspension flow rate in the first zone is 0.8 m/s to 1.5 m/s and the residence time is 1.0 s to 1.5 s. In the second zone the obtained mixture is diluted by 400 to 500 times with a suspension of calcium hydroxide. The diluted mixture is returned to the first zone and the process is repeated thereby ensuring a 4 to 5 fold circulation of the complete volume of the mixture during 10 to 20 min. After the feeding of acid is terminated the obtained suspension of the product is stirred for additionally 10 to 12 min. The resulting suspension of hydroxylapatite has a concentration of 4.5% to 5.0%. Additionally, the suspension may be dried to produce solid hydroxylapatite or dehydrated by centrifugation to produce a suspension of hydroxylapatite having a concentration of 18% to 33%.