Patent US2523786A successfully refreshed from Google Patents.
Patent US3929964A successfully refreshed from Google Patents.
US3929964A
Expired / Lapsed
US
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Process for the conversion of sodium sulfite
Assignee: Individual
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Filing: 1974-09-23
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Granted: 1975-12-30
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Expires: 1994-09-23
Abstract
Abstract The sodium sulfite obtained as a byproduct in the production of hydroxy aromatic compounds from aromatic hydrocarbons, sulfur trioxide and sodium hydroxide, is converted into sulfur trioxide and sodium hydroxide for recirculation of same in said production of hydroxy aromatic compounds, by a process wherein: (a) the sodium sulfite is reacted with zinc chloride to form sodium chloride and zinc sulfite; (b) the zinc sulfite is heated to form zinc oxide and sulfur dioxide and the sulfur dioxide is oxidized to sulfur trioxide; (c) the sodium chloride is reacted with ammonium bicarbonate to form ammonium chloride and sodium bicarbonate; (d) the zinc oxide is reacted with the ammonium chloride to form zinc chloride and ammonia; (e) the ammonia is reacted in the Solvay Process to form ammonium bicarbonate; and (f) the sodium bicarbonate is heated to form sodium carbonate and carbon dioxide, and the sodium carbonate is reacted with calcium oxide to form sodium hydroxide.
Inventors
- 👤 Matthias Thoma
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:03
CPC Classifications
C; C01; C01B; C01B17/00; C01B17/48; C01D; C01D1/00; C01D1/04; C01D1/20
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
129 words
A PROCESS FOR THE CONVERSION OF SODIUM SULFITE, OBTAINED IN THE PRODUCTION OF HYDROXY AROMATICS, INTO SODIUM HYDROXIDE AND SULPHUR TRIOXIDE FOR RECIRCULATION IN SAID PRODUCTION OF HYDROXY AROMATICS, WHICH COMPRISES: A. REACTING SAID SODIUM SULFITE WITH ZINC CHLORIDE TO FORM SODIUM CHLORIDE AND ZINC SULFITE, B. HEATING SAID ZINC SULFITE TO FORM ZINC OXIDE AND SULPHUR DIOXIDE AND OXIDIZING SAID SULFUR DIOXIDE TO SULPHUR TRIOXIDE, C. REACTING SAID SODIUM CHLORIDE WITH AMMONIUM BICORBONATE TO FORM AMMONIUM CHLORIDE AND SODIUM BICARBONATE, D. REACTING SAID ZINC OXIDE WITH SAID AMMONIUM CHLORIDE TO FORM ZINC CHLORIDE AND AMMONIA, E. CONVERTING SAID AMMONIA TO FORM AMMONIUM BICARBONATE, AND F. HEATING SAID SODIUM BICARBONATE TO FORM SODIUM CARBONATE AND CARBON DIOXIDE, AND REACTING SAID SODIUM CARBONATE WITH CALCIUM OXIDE TO FORM SODIUM HYDROXIDE.
Claim 2
Dependent Claim
129 words
A PROCESS FOR THE CONVERSION OF SODIUM SULFITE, OBTAINED IN THE PRODUCTION OF HYDROXY AROMATICS, INTO SODIUM HYDROXIDE AND SULPHUR TRIOXIDE FOR RECIRCULATION IN SAID PRODUCTION OF HYDROXY AROMATICS, WHICH COMPRISES: A. REACTING SAID SODIUM SULFITE WITH ZINC CHLORIDE TO FORM SODIUM CHLORIDE AND ZINC SULFITE, B. HEATING SAID ZINC SULFITE TO FORM ZINC OXIDE AND SULPHUR DIOXIDE AND OXIDIZING SAID SULFUR DIOXIDE TO SULPHUR TRIOXIDE, C. REACTING SAID SODIUM CHLORIDE WITH AMMONIUM BICORBONATE TO FORM AMMONIUM CHLORIDE AND SODIUM BICARBONATE, D. REACTING SAID ZINC OXIDE WITH SAID AMMONIUM CHLORIDE TO FORM ZINC CHLORIDE AND AMMONIA, E. CONVERTING SAID AMMONIA TO FORM AMMONIUM BICARBONATE, AND F. HEATING SAID SODIUM BICARBONATE TO FORM SODIUM CARBONATE AND CARBON DIOXIDE, AND REACTING SAID SODIUM CARBONATE WITH CALCIUM OXIDE TO FORM SODIUM HYDROXIDE.
Claim 3
Dependent Claim
24 words
A process as in claim 1 wherein the zinc chloride produced in step (d) is recirculated for reaction with sodium sulfite in step (a).
Claim 4
Dependent Claim
24 words
A process as in claim 1 wherein the ammonium bicarbonate produced in step (e) is recirculated for reaction with sodium chloride in step (c).
Claim 5
Dependent Claim
45 words
A process as in claim 1 wherein calcium carbonate is produced along with sodium hydroxide in step (f), said calcium carbonate is heated to form calcium oxide and carbon dioxide, and said calcium oxide is recirculated for reaction with additional sodium carbonate in step (f).
Claim 6
Dependent Claim
60 words
A process as in claim 1 wherein sodium sulfate is present with sodium sulfite in the starting composition and is carried through step (a) in admixture with said sodium chloride, and wherein prior to step (b), said sodium sulfate in the admixture is reacted with calcium chloride to form sodium chloride and calcium sulfate, said calcium sulfate then being separated.
Claim 7
Dependent Claim
118 words
In a process for the conversion of sodium sulfite, obtained in the production of hydroxy aromatics, into sodium carbonate and sulfur trioxide, for recirculation in said production of hydroxy aromatics, which comprises: a. reacting said sodium sulfite wich zinc chloride to form sodium chloride and zinc sulfite, b. heating said zinc sulfite to form zinc oxide and sulphur dioxide and oxidizing said sulfur dioxide to sulphur trioxide, c. reacting said sodium chloride with ammonium bicarbonate to form ammonium chloride and sodium bicarbonate, d. reacting said zinc oxide with said ammonium chloride to form zinc chloride and ammonia, e. converting said ammonia to form ammonium bicarbonate, and f. heating said sodium bicarbonate to form sodium carbonate and carbon dioxide.
Claim 8
Dependent Claim
118 words
In a process for the conversion of sodium sulfite, obtained in the production of hydroxy aromatics, into sodium carbonate and sulfur trioxide, for recirculation in said production of hydroxy aromatics, which comprises: a. reacting said sodium sulfite wich zinc chloride to form sodium chloride and zinc sulfite, b. heating said zinc sulfite to form zinc oxide and sulphur dioxide and oxidizing said sulfur dioxide to sulphur trioxide, c. reacting said sodium chloride with ammonium bicarbonate to form ammonium chloride and sodium bicarbonate, d. reacting said zinc oxide with said ammonium chloride to form zinc chloride and ammonia, e. converting said ammonia to form ammonium bicarbonate, and f. heating said sodium bicarbonate to form sodium carbonate and carbon dioxide.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-29 | 1979-06-30 | 1979-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-29 | 1983-06-30 | 1983-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-29 | 1987-06-30 | 1987-12-30 | $7700.00 | Window Closed / Lapsed |