US3963586A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Extractive distillation of a dimethyl carbonate feed with water
Assignee: SnamProgetti SpA
•
Filing: 1974-10-25
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Granted: 1976-06-15
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Expires: 1994-10-25
Abstract
Abstract Dimethyl carbonate is separated from a mixture thereof with methyl alcohol and water through an extractive distillation process wherein water is utilized as the solvent.
Inventors
- 👤 Alessandro Ginnasi
- 👤 Giovanni Passoni
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:34
CPC Classifications
C; C07; C07C; C07C68/00; C07C68/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
104 words
The process of separating dimethyl carbonate from a mixture thereof with methyl alcohol and water through an extractive distillation comprising the steps of feeding said mixture to an intermediate zone of an extractive distillation column, feeding solvent water in an amount equal to at least 10 times the column reflux rate to said column at a point in proximity to its top, withdrawing a stream of methyl alcohol and water from the bottom of said column, withdrawing from the top of said column a stream having an organic phase containing dimethylcarbonate and an aqueous phase, and separating said organic phase from the aqueous phase.
Claim 2
Dependent Claim
104 words
The process of separating dimethyl carbonate from a mixture thereof with methyl alcohol and water through an extractive distillation comprising the steps of feeding said mixture to an intermediate zone of an extractive distillation column, feeding solvent water in an amount equal to at least 10 times the column reflux rate to said column at a point in proximity to its top, withdrawing a stream of methyl alcohol and water from the bottom of said column, withdrawing from the top of said column a stream having an organic phase containing dimethylcarbonate and an aqueous phase, and separating said organic phase from the aqueous phase.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-15 | 1979-12-15 | 1980-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-15 | 1983-12-15 | 1984-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-15 | 1987-12-15 | 1988-06-15 | $7700.00 | Window Closed / Lapsed |