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US3288687A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the purification of epsilon- caprolactam by dilution, acidulation and distillation

Assignee: —
•
Filing: —
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Granted: 1966-11-29
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Expires: 1983-11-29
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Abstract

No abstract record available.

Inventors

No inventors recorded.

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 03:15
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/148; C07C7/17; C07C7/171; C07D; C07D201/00; C07D201/02; C07D201/08; C07D201/16; C07D223/00; C07D223/02; C07D223/06; C07D223/08; C07D223/10

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 74 words
A PROCESS FOR THE PURIFICATION OF CRUDE EPSILON-CAPROLACTAM COMPRISING THE STEPS OF DILUTING SAID CRUDE EPSILONCAPROLCATAM WITH WATER IN THE PROPORTION OF APPROXIMATELY 2 PARTS ADDED WATER TO 5 PARTS CRUDE EPSILONCAPROLACTAM, ACIDULATING THE RESULTANT CRUDE TO A PH RANGE OF 3.2 TO 4.2 WITH AN ADDITIVE CONSISTING ESSENTIALLY OF SULFURIC ACID, SUBJECTING THE RESULTANT MIXTURE TO DISTILLATION TO VAPORIZE THE WATER CONTAINED IN SAID CRUDE CAPROLACTAM, AND SUBJECTING THE RESULTANT CAPROLACTAM TO RECTIFICATION.
Claim 2
Dependent Claim 74 words
A PROCESS FOR THE PURIFICATION OF CRUDE EPSILON-CAPROLACTAM COMPRISING THE STEPS OF DILUTING SAID CRUDE EPSILONCAPROLCATAM WITH WATER IN THE PROPORTION OF APPROXIMATELY 2 PARTS ADDED WATER TO 5 PARTS CRUDE EPSILONCAPROLACTAM, ACIDULATING THE RESULTANT CRUDE TO A PH RANGE OF 3.2 TO 4.2 WITH AN ADDITIVE CONSISTING ESSENTIALLY OF SULFURIC ACID, SUBJECTING THE RESULTANT MIXTURE TO DISTILLATION TO VAPORIZE THE WATER CONTAINED IN SAID CRUDE CAPROLACTAM, AND SUBJECTING THE RESULTANT CAPROLACTAM TO RECTIFICATION.

References Cited (Backward Citations)

US2605261A Cited
US2752336A Cited
US2939865A Cited
US2993889A Cited
US3016375A Cited
US3016376A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1969-11-28 1970-05-30 1970-11-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1973-11-28 1974-05-30 1974-11-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1977-11-28 1978-05-30 1978-11-29 $7700.00 Window Closed / Lapsed

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