FR2134514A1 - Pure pyromellitic dianhydride - from oxidn of tetraalkylbenzene with purification of intermediate pyromellitic acid - Google Patents

Pure pyromellitic dianhydride - from oxidn of tetraalkylbenzene with purification of intermediate pyromellitic acid

Info

Publication number
FR2134514A1
FR2134514A1 FR7214716A FR7214716A FR2134514A1 FR 2134514 A1 FR2134514 A1 FR 2134514A1 FR 7214716 A FR7214716 A FR 7214716A FR 7214716 A FR7214716 A FR 7214716A FR 2134514 A1 FR2134514 A1 FR 2134514A1
Authority
FR
France
Prior art keywords
pyromellitic
pure
acid
tetraalkylbenzene
dianhydride
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
FR7214716A
Other languages
French (fr)
Other versions
FR2134514B1 (en
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.)
Prolizenz AG
Original Assignee
Prolizenz AG
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 Prolizenz AG filed Critical Prolizenz AG
Publication of FR2134514A1 publication Critical patent/FR2134514A1/en
Application granted granted Critical
Publication of FR2134514B1 publication Critical patent/FR2134514B1/fr
Granted legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/42—Separation; Purification; Stabilisation; Use of additives
    • C07C51/43—Separation; Purification; Stabilisation; Use of additives by change of the physical state, e.g. crystallisation
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/16—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation
    • C07C51/21—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen
    • C07C51/255—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen of compounds containing six-membered aromatic rings without ring-splitting
    • C07C51/265—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen of compounds containing six-membered aromatic rings without ring-splitting having alkyl side chains which are oxidised to carboxyl groups
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/54—Preparation of carboxylic acid anhydrides
    • C07C51/56—Preparation of carboxylic acid anhydrides from organic acids, their salts, their esters or their halides, e.g. by carboxylation

Abstract

Pure pyromellitic dianhydride is prepd. by (a) oxidising a 1,2,4,5-tetraalkylbenzene catalytically in the aqs. phase, (b) transforming the pyromellitic dianhydride present in the reaction gas into pyromellitic acid, (c) purifying this acid by crystallisation from an aqs. soln., and (d) converting the pure acid into the dianhydride by dehydration. Prod. is esp. suitable for prepn. of high quality resins with good electrical properties and a good resistance to heat and chemicals.
FR7214716A 1971-04-26 1972-04-25 Pure pyromellitic dianhydride - from oxidn of tetraalkylbenzene with purification of intermediate pyromellitic acid Granted FR2134514A1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CH525871A CH540217A (en) 1971-04-26 1971-04-26 Process for the production of pure pyromellitic dianhydride

Publications (2)

Publication Number Publication Date
FR2134514A1 true FR2134514A1 (en) 1972-12-08
FR2134514B1 FR2134514B1 (en) 1975-06-20

Family

ID=4290581

Family Applications (1)

Application Number Title Priority Date Filing Date
FR7214716A Granted FR2134514A1 (en) 1971-04-26 1972-04-25 Pure pyromellitic dianhydride - from oxidn of tetraalkylbenzene with purification of intermediate pyromellitic acid

Country Status (8)

Country Link
BE (1) BE781732A (en)
CH (1) CH540217A (en)
DE (1) DE2151238A1 (en)
ES (1) ES401989A1 (en)
FR (1) FR2134514A1 (en)
IT (1) IT953752B (en)
NL (1) NL7205522A (en)
ZA (1) ZA722810B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1199298A1 (en) * 2000-08-23 2002-04-24 Mitsubishi Gas Chemical Company, Inc. Process for producing refined pyromellitic acid and refined pyromellitic anhydride

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1199298A1 (en) * 2000-08-23 2002-04-24 Mitsubishi Gas Chemical Company, Inc. Process for producing refined pyromellitic acid and refined pyromellitic anhydride
US6579990B2 (en) 2000-08-23 2003-06-17 Mitsubishi Gas Chemical Company, Inc. Process for producing refined pyromellitic acid and refined pyromellitic anhydride

Also Published As

Publication number Publication date
FR2134514B1 (en) 1975-06-20
ES401989A1 (en) 1975-03-01
BE781732A (en) 1972-07-31
CH540217A (en) 1973-08-15
DE2151238A1 (en) 1972-12-21
IT953752B (en) 1973-08-10
ZA722810B (en) 1973-02-28
NL7205522A (en) 1972-10-30

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Legal Events

Date Code Title Description
ST Notification of lapse