JPS5724357A - Recovery of epsilon-caprolactam from lactam solution containing epsilon-caprolactam oligomer - Google Patents

Recovery of epsilon-caprolactam from lactam solution containing epsilon-caprolactam oligomer

Info

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
Application number
JP9775880A
Other languages
Japanese (ja)
Other versions
JPS6021582B2 (en
Inventor
Katsuaki Fujiwara
Ryozo Kondo
Tsutomu Setsuda
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toray Industries Inc
Original Assignee
Toray Industries Inc
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Toray Industries Inc filed Critical Toray Industries Inc
Priority to JP9775880A priority Critical patent/JPS6021582B2/en
Publication of JPS5724357A publication Critical patent/JPS5724357A/en
Publication of JPS6021582B2 publication Critical patent/JPS6021582B2/en
Expired legal-status Critical Current

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
JP9775880A 1980-07-17 1980-07-17 Method for recovering ε-caprolactam from a lactam solution containing ε-caprolactam oligomer Expired JPS6021582B2 (en)

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)

* Cited by examiner, † Cited by third party
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

Cited By (2)

* Cited by examiner, † Cited by third party
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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