Patent US4837002A successfully refreshed from Google Patents.
US4837002A
Expired / Lapsed
US
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Removal of chlorate from caustic soda
Assignee: BASF SE
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Filing: 1988-02-22
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Granted: 1989-06-06
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Expires: 2008-02-22
Abstract
Abstract Chlorate is removed from aqueous caustic soda by reducing with iron pentacarbonyl and separating off the resulting iron oxide containing precipitate.
Inventors
- 👤 Dieter Schlaefer
- 👤 Wolfgang Kochanek
- 👤 Bernd Leutner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 06:38
CPC Classifications
C; C01; C01G; C01G49/00; C01G49/02; C01G49/08; C01D; C01D1/00; C01D1/04; C01D1/28; C25; C25B; C25B15/00; C25B15/08; C25B15/085
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
32 words
A process for removing chlorate from aqueous caustic soda by reducing with an iron compound and separating off the resulting iron oxide containing precipitate, which comprises using iron pentacarbonyl as reducing agent.
Claim 2
Dependent Claim
32 words
A process for removing chlorate from aqueous caustic soda by reducing with an iron compound and separating off the resulting iron oxide containing precipitate, which comprises using iron pentacarbonyl as reducing agent.
Claim 3
Dependent Claim
25 words
A process as claimed in claim 1, wherein from 0.5 to 3 moles of iron pentacarbonyl are used per mole of chlorate to be reduced.
Claim 4
Dependent Claim
27 words
A process as claimed in claim 1, wherein the reaction is carried out within the range from 20° C. to the boiling point of the caustic soda.
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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) | 1992-06-05 | 1992-12-05 | 1993-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-05 | 1996-12-05 | 1997-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-05 | 2000-12-05 | 2001-06-06 | $7700.00 | Window Closed / Lapsed |