Multi-stage process for the preparation of sodium bicarbonate
Abstract
Abstract SODIUM BICARBONATE IS PRODUCED FROM AN AQUEOUS SOLUTION OF SODIUM HYDROXIDE OBTAINED FROM THE SODIUM AMALGAM ELECTROLYTIC PROCESS BY: (A) REACTING THE SODIUM HYDROXIDE SOLUTION WITH CARBON DIOXIDE AT ABOUT 70-110*C., PREFERABLY 95-105*C., IN A FIRST STAGE TO FORM A CRYSTALLINE PRECIPITATE CONTAINING SODIUM CARBONATE MONOHYDRATE WHILE SIMULTANEOUSLY EVAPORATING WATER FROM THE REACTION MIXTURE; (B) SEPARATING THE CRYSTALLINE PRECIPITATE FROM MOTHER LIQUOR THEREOF AND RECYCLING THE LATTER TO THE FIRST STAGE; (C) IN A SECOND STAGE, DISSOLVING THE SEPARATED CRYSTALLINE PRECIPITATE CONTAINING SODIUM CARBONATE MONOHYDRATE, AND REACTING THE RESULTANT SOLUTON WITH CARBON DIOXIDE AT 20-70*C., PREFERABLY 30-40*C., TO PRECIPITATE SODIUM BICARBONATE; (D) SEPARATING THE RESULTANT SOLID SODIUM BIICARBONATE FROM MOTHER LIQUOR, AND RECYCLING THE LATTER INTO THE SECOND STAGE TO DISSOLVE SAID CRYSTALLINE PRECIPITATE.
Inventors
- 👤 U Neumann
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-06 | 1977-02-05 | 1977-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-06 | 1981-02-05 | 1981-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-06 | 1985-02-05 | 1985-08-07 | $7700.00 | Window Closed / Lapsed |