Global patent index - EP 1027319 A1

EP 1027319 A1 2000-08-16 - FORMING TEREPHTHALIC ACID BY ELECTROCHEMICAL ACIDIFICATION OF A SODIUM TEREPHTHALATE SOLUTION

Title (en)

FORMING TEREPHTHALIC ACID BY ELECTROCHEMICAL ACIDIFICATION OF A SODIUM TEREPHTHALATE SOLUTION

Title (de)

GEWINNUNG VON TEREPHTHALSÄURE DURCH ELEKTROCHEMISCHE ANSÄURUNG EINER NATRIUMTEREPHTALAT-LÖSUNG

Title (fr)

FORMATION DE L'ACIDE TEREPHTALIQUE PAR ACIDIFICATION ELECTROCHIMIQUE D'UNE SOLUTION DE TEREPHTALATE DE SOUDE

Publication

EP 1027319 A1 (FR)

Application

EP 98941522 A

Priority

  • FR 9801722 W
  • FR 9710095 A

Abstract (en)

[origin: FR2767131A1] The invention concerns a method for recuperating from saponification products of alkylene polyterephthalate with soda, both terephthalate ions in acid form and sodium ions in the form of soda and for optimising the recuperation process. The invention is characterised in that the sodium terephthalate solution resulting from dissolving these saponification products are subjected to a step of electrochemical pre-acidification to bring it to a pH of 4 to 7, then an electrochemical acidification by electrolysis to precipitate the terephthalic acid in the anode section and recuperate in the cathode the soda which can be recycled, if required, after being previously concentrated, to the step of saponification.

IPC 1-7 (main, further and additional classification)

C07C 51/02; C07C 63/26; C25B 3/00

IPC 8 full level (invention and additional information)

C07C 51/02 (2006.01); C25B 1/16 (2006.01); C25B 3/00 (2006.01)

CPC (invention and additional information)

C25B 3/00 (2013.01); C07C 51/02 (2013.01); C25B 1/16 (2013.01)

Combination set (CPC)

  1. C07C 51/02 + C07C 63/26
  2. C07C 51/02 + C07C 63/38

Citation (search report)

See references of WO 9907663A1

Designated contracting state (EPC)

AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

EPO simple patent family

FR 2767131 A1 19990212; FR 2767131 B1 19991022; AU 8986998 A 19990301; EP 1027319 A1 20000816; US 6312582 B1 20011106; WO 9907663 A1 19990218

INPADOC legal status

2002-09-18 [18D] DEEMED TO BE WITHDRAWN

- Ref Legal Event Code: 18D

- Effective date: 20020226

2001-09-05 [17Q] FIRST EXAMINATION REPORT

- Ref Legal Event Code: 17Q

- Effective date: 20010717

2000-08-16 [17P] REQUEST FOR EXAMINATION FILED

- Ref Legal Event Code: 17P

- Effective date: 20000125

2000-08-16 [AK] DESIGNATED CONTRACTING STATES:

- Ref Legal Event Code: AK

- Designated State(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE