反应详情

温度

45 °C

To a 22% (w/w) unprocessed aqueous solution of 6160 g (about 12.2 mol) sodium N-methylglycinate, 20% sulfuric acid was added under stirring and cooling in an ice-salt liquor bath to adjusting the pH to 9.8. The temperature was kept below 15° C. in this process. Under the condition that the internal temperature was kept at 40° C., 3052 g (11 mol) of S-methylisothiourea sulfate was slowly added into the solution under stirring within 100 minutes. Then the solution was further stirred for 15 minutes at an internal temperature not more than 40° C. Thereafter, a hot vapor was fed into the solution for 45 minutes, and a crystal was precipitated. After staying for 7 hours, the solution was centrifuged to remove the mother liquor, then was washed with distilled water several times (80 ml each time) until pH value becomes to ≦7.6. The product was washed once with 1100 ml of 95% ethanol to obtain a crude product. 1260 ml of water was added to the crude product, and the mixture was heated to 45° C. under stirring. Then pH was adjusted to 7.0 with addition of 10% sulfuric acid. Thereafter, the temperature was raised to 80° C. Then 0.5 g of disodium EDTA was added thereto, and the temperature was raised to 90° C. After stirring for 15 minutes, the solution was filtered. The filtrate was cooled to a temperature below 20° C., and a crystal was obtained. The crystalline product was recovered by centrifugation, washed once with 50 ml of distilled water and once with 70 ml of 95% ethanol, and dried in a vacuum drier at 40° C. under 20 millibar pressure. 1044 g of the product (S-methylisothiourea was used as the standard) was obtained. The yield of creatine-monohydrate was 70.3, and the content or purity (HPLC) was 99.4%. After dehydrated at 80° C., creatine was obtained. There was substantially no product loss in this process.

1. temperaturecooling in an ice-salt liquor bath
2. customwas kept below 15° C. in this process
3. customwas kept at 40° C.
4. stirringunder stirring within 100 minutes
5. stirringThen the solution was further stirred for 15 minutes at an internal temperature not more than 40° C
6. customa crystal was precipitated
7. waitAfter staying for 7 hours
8. customto remove the mother liquor
9. washwas washed with distilled water several times (80 ml each time) until pH value
10. washThe product was washed once with 1100 ml of 95% ethanol
11. customto obtain a crude product
12. stirringunder stirring
13. temperatureThereafter, the temperature was raised to 80° C
14. temperaturethe temperature was raised to 90° C
15. stirringAfter stirring for 15 minutes
16. filtrationthe solution was filtered
17. temperatureThe filtrate was cooled to a temperature below 20° C.
18. customa crystal was obtained
19. customThe crystalline product was recovered by centrifugation
20. washwashed once with 50 ml of distilled water and once with 70 ml of 95% ethanol
21. customdried in a vacuum drier at 40° C. under 20 millibar pressure
22. customwas obtained
23. customAfter dehydrated at 80° C.