US2646393A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the purification of dimethyl terephthalate by distillation
Assignee: EIDP Inc
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Filing: 1952-06-21
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Granted: 1953-07-21
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Expires: 1972-06-21
Abstract
No abstract record available.
Inventors
- 👤 Hughes Jesse Edward
- 👤 Kemp Harold Steen
- 👤 Pyle Cyrus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:21
CPC Classifications
C; C07; C07C; C07C67/00; C07C67/48; C07C67/52; C07C67/54
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
152 words
A CONTINUOUS PROCESS FOR THE DISTILLATION PURIFICATION OF DIMETHYL TEREPHTHALATE CONTAMINATED WITH XYLENE, METHYL HYDROGEN TEREPHTHALATE AND LOW-BOILING IMPURITIES, INCLUDING METHYL BENZOATE AND OTHER LOW BOILERS, COMPRISING INTRODUCING THE IMPURE MATERIAL INTO A FIRST DISTILLATION ZONE, DISTILLING SAID IMPURE MATERIAL IN SAID FIRST INSTALLATION ZONE AND REMOVING SUBSTANTIALLY ALL OF SAID XYLENE AS A FIRST VAPOROUS OVERHEAD PRODUCT, CONDENSING SAID FIRST VAPOROUS OVERHEAD PRODUCT AND RETURNING A PORTION THEREOF TO SAID FIRST DISTILLATION ZONE AS REFLUX, WITHDRAWING A FIRST BOTTOM PRODUCT FROM SAID FIRST DISTILLATION ZONE AND INTRODUCING SAID FIRST BOTTOM PRODUCT INTO A SECOND DISTILLATION ZONE, DISTILLING SAID FIRST BOTTOM PRODUCT IN SAID SECOND DISTILLATION ZONE AND REMOVING A SUBSTANTIAL AMOUNT OF SAID LOW-BOILING IMPURITIES TOGETHER WITH REMAINING XYLENE AS A SECOND VAPOROUS OVERHEAD PRODUCT FROM SAID SECOND DISTILLATION ZONE, CONDENSING SAID SECOND VAPOROUS OVERHEAD PRODUCT AND RETURNING A PORTION THEREOF AS REFLUX TO SAID SECOND DISTILLATION ZONE, WITHDRAWING A SECOND
Claim 2
Dependent Claim
152 words
A CONTINUOUS PROCESS FOR THE DISTILLATION PURIFICATION OF DIMETHYL TEREPHTHALATE CONTAMINATED WITH XYLENE, METHYL HYDROGEN TEREPHTHALATE AND LOW-BOILING IMPURITIES, INCLUDING METHYL BENZOATE AND OTHER LOW BOILERS, COMPRISING INTRODUCING THE IMPURE MATERIAL INTO A FIRST DISTILLATION ZONE, DISTILLING SAID IMPURE MATERIAL IN SAID FIRST INSTALLATION ZONE AND REMOVING SUBSTANTIALLY ALL OF SAID XYLENE AS A FIRST VAPOROUS OVERHEAD PRODUCT, CONDENSING SAID FIRST VAPOROUS OVERHEAD PRODUCT AND RETURNING A PORTION THEREOF TO SAID FIRST DISTILLATION ZONE AS REFLUX, WITHDRAWING A FIRST BOTTOM PRODUCT FROM SAID FIRST DISTILLATION ZONE AND INTRODUCING SAID FIRST BOTTOM PRODUCT INTO A SECOND DISTILLATION ZONE, DISTILLING SAID FIRST BOTTOM PRODUCT IN SAID SECOND DISTILLATION ZONE AND REMOVING A SUBSTANTIAL AMOUNT OF SAID LOW-BOILING IMPURITIES TOGETHER WITH REMAINING XYLENE AS A SECOND VAPOROUS OVERHEAD PRODUCT FROM SAID SECOND DISTILLATION ZONE, CONDENSING SAID SECOND VAPOROUS OVERHEAD PRODUCT AND RETURNING A PORTION THEREOF AS REFLUX TO SAID SECOND DISTILLATION ZONE, WITHDRAWING A SECOND
References Cited (Backward Citations)
US2459014A
Cited
US2491660A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-07-20 | 1957-01-19 | 1957-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-07-20 | 1961-01-19 | 1961-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-07-20 | 1965-01-19 | 1965-07-21 | $7700.00 | Window Closed / Lapsed |