JPS5724357A - Recovery of epsilon-caprolactam from lactam solution containing epsilon-caprolactam oligomer - Google Patents
Recovery of epsilon-caprolactam from lactam solution containing epsilon-caprolactam oligomerInfo
- Publication number
- JPS5724357A JPS5724357A JP9775880A JP9775880A JPS5724357A JP S5724357 A JPS5724357 A JP S5724357A JP 9775880 A JP9775880 A JP 9775880A JP 9775880 A JP9775880 A JP 9775880A JP S5724357 A JPS5724357 A JP S5724357A
- Authority
- JP
- Japan
- Prior art keywords
- caprolactam
- epsilon
- oligomer
- solution containing
- caustic alkali
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Other In-Based Heterocyclic Compounds (AREA)
- Polyamides (AREA)
Abstract
PURPOSE: In recovering ε-caprolactam from a lactam solution containing ε-caprolactam oligomer, to improve the purity and yield of ε-caprolactam, by adding caustic alkali in rectification process without adding the caustic alkali in distillation process.
CONSTITUTION: A lactam solution containing ε-caprolactam oligomer is distilled without adding caustic alkali to it, and the solution is separated into a distillation residue consisting essentially of the oligomer and ε-caprolactam. The residue is depolymerized in the presence of phosphoric acid and overheated steam, so that ε- caprolactam is recovered in the form of an aqueous solution. 0.01W0.5pts.wt. caustic alkali (e.g., NaOH, KOH, etc.) based on 100pts.wt. solution obtained in the distillation process is added to ε-caprolactam prepared in the process, and it is rectified to give ε-caprolactam.
COPYRIGHT: (C)1982,JPO&Japio
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9775880A JPS6021582B2 (en) | 1980-07-17 | 1980-07-17 | Method for recovering ε-caprolactam from a lactam solution containing ε-caprolactam oligomer |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9775880A JPS6021582B2 (en) | 1980-07-17 | 1980-07-17 | Method for recovering ε-caprolactam from a lactam solution containing ε-caprolactam oligomer |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS5724357A true JPS5724357A (en) | 1982-02-08 |
JPS6021582B2 JPS6021582B2 (en) | 1985-05-28 |
Family
ID=14200771
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP9775880A Expired JPS6021582B2 (en) | 1980-07-17 | 1980-07-17 | Method for recovering ε-caprolactam from a lactam solution containing ε-caprolactam oligomer |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS6021582B2 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63218046A (en) * | 1987-03-06 | 1988-09-12 | 日本カーバイド工業株式会社 | Daily-need vessels |
US5227028A (en) * | 1990-07-06 | 1993-07-13 | Dsm N.V. | Process for treating amides |
-
1980
- 1980-07-17 JP JP9775880A patent/JPS6021582B2/en not_active Expired
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63218046A (en) * | 1987-03-06 | 1988-09-12 | 日本カーバイド工業株式会社 | Daily-need vessels |
US5227028A (en) * | 1990-07-06 | 1993-07-13 | Dsm N.V. | Process for treating amides |
Also Published As
Publication number | Publication date |
---|---|
JPS6021582B2 (en) | 1985-05-28 |
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