US3137707A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of benzene carboxylic acids and anhydrides
Assignee: Union Oil Company of California
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Filing: 1961-06-26
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Granted: 1964-06-16
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Expires: 1981-06-26
Abstract
No abstract record available.
Inventors
- 👤 William D Schaeffer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:36
CPC Classifications
C; C07; C07C; C07C63/00; C07C63/04; C07C51/00; C07C51/16; C07C51/21
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
126 words
A METHOD FOR PREPARING TEREPHTHALIC ACID WHICH COMPRISES SUBJECTING TOLUENE TO AMIDOMETHYLATION WITH N-METHYLOLACETAMIDE IN THE PRESENCE OF (U) AN ACIDIC CONDENSATION CATALYSST, AND (2) A SOLVENT WHICH IS ESSENTIALLY ACETIC ACID, AT A TEMPERATURE BETWEEN ABOUT 0* AND 200*C., TO THEREBY PRODUCE ORTHO- AND PARA-ACETAMIDOMETHYL TOLUENE, REMOVING SAID ACIDIC CONDENSATION CATALYST FROM THE REACTION PRODUCT AND THEN SUBJECTING THE REMAINING MIXTURE OF ORTHO- AND PARA-ACETAMIDOMETHYL TOLUENES TO OXIDATION WITH AN ADDED OXIDIZING AGENT IN THE PRESENCE OF SAID ACETIC ACID SOLVENT, AND RECOVERING FROM THE OXIDATION MIXTURE O-PHTHALIC ACID, TEREPHTHALIC ACID AND ACETIC ACID, REACTING A PORTION OF THE ACETIC ACID RECOVERED FROM SAID OXIDATION STEP WITH AMMONIA AND FORMALDEHYDE TO PRODUCE N-METHYLOLACETAMIDE, AND RECYCLING AND N-METHYLOLACETAMIDE PLUS EXCESS ACETIC ACID TO SAID AMIDOMETHYLATION STEP.
Claim 2
Independent Claim
126 words
A METHOD FOR PREPARING TEREPHTHALIC ACID WHICH COMPRISES SUBJECTING TOLUENE TO AMIDOMETHYLATION WITH N-METHYLOLACETAMIDE IN THE PRESENCE OF (U) AN ACIDIC CONDENSATION CATALYSST, AND (2) A SOLVENT WHICH IS ESSENTIALLY ACETIC ACID, AT A TEMPERATURE BETWEEN ABOUT 0* AND 200*C., TO THEREBY PRODUCE ORTHO- AND PARA-ACETAMIDOMETHYL TOLUENE, REMOVING SAID ACIDIC CONDENSATION CATALYST FROM THE REACTION PRODUCT AND THEN SUBJECTING THE REMAINING MIXTURE OF ORTHO- AND PARA-ACETAMIDOMETHYL TOLUENES TO OXIDATION WITH AN ADDED OXIDIZING AGENT IN THE PRESENCE OF SAID ACETIC ACID SOLVENT, AND RECOVERING FROM THE OXIDATION MIXTURE O-PHTHALIC ACID, TEREPHTHALIC ACID AND ACETIC ACID, REACTING A PORTION OF THE ACETIC ACID RECOVERED FROM SAID OXIDATION STEP WITH AMMONIA AND FORMALDEHYDE TO PRODUCE N-METHYLOLACETAMIDE, AND RECYCLING AND N-METHYLOLACETAMIDE PLUS EXCESS ACETIC ACID TO SAID AMIDOMETHYLATION STEP.
Claim 3
Dependent Claim
126 words
THE PROCESS FOR PREPARING PYROMELLITIC ANHYDRIDE WHICH COMPRISES REACTING PSEUDOCUMENE WITH AN AMIDE SELECTED FROM THE CLASS CONSISTING OF N-METHYLOFORMAMIDE AND N-METHYLOL-ACETAMIDE, SAID REACTION BEING CARRIED OUT IN THE LIQUID PHASE AT A REACTION TEMPERATURE BETWEEN ABOUT 0*C. AND ABOUT 200*C. IN THE PRESENCE OF A CATALYTIC AMOUNT OF A STRONG ACID CONDENSATION CATALYST; RECOVERING A PRODUCT SELECTED FROM THE CLASS CONSISTING OF N(2,4,5-TRIMETHYL)-BENZYL-FORMAMIDE AND N-(2,4,5-TRIMETHYL)-BENZYL-ACETAMIDE FROM THE REACTION MIXTURE SO OBTAINED; SUBJECTING SAID RECOVERED PRODUCT TO OXIDATION IN THE VAPOR PHASE WITH A FREE OXYGEN-CONTAINING GAS IN THE PRESENCE OF AN OXIDATION CATALYST SELECTED FROM THE CLASS CONSISTING OF THE OXIDES AND SALTS OF THE METALS OF GROUPS V AND VIII, INCLUSIVE, OF THE PERIODIC TABLE; AND RECOVERING PYROMELLITIC ANHYDRIDE FROM THE CRUDE OXIDATION PRODUCT.
Claim 4
Dependent Claim
126 words
THE PROCESS FOR PREPARING PYROMELLITIC ANHYDRIDE WHICH COMPRISES REACTING PSEUDOCUMENE WITH AN AMIDE SELECTED FROM THE CLASS CONSISTING OF N-METHYLOFORMAMIDE AND N-METHYLOL-ACETAMIDE, SAID REACTION BEING CARRIED OUT IN THE LIQUID PHASE AT A REACTION TEMPERATURE BETWEEN ABOUT 0*C. AND ABOUT 200*C. IN THE PRESENCE OF A CATALYTIC AMOUNT OF A STRONG ACID CONDENSATION CATALYST; RECOVERING A PRODUCT SELECTED FROM THE CLASS CONSISTING OF N(2,4,5-TRIMETHYL)-BENZYL-FORMAMIDE AND N-(2,4,5-TRIMETHYL)-BENZYL-ACETAMIDE FROM THE REACTION MIXTURE SO OBTAINED; SUBJECTING SAID RECOVERED PRODUCT TO OXIDATION IN THE VAPOR PHASE WITH A FREE OXYGEN-CONTAINING GAS IN THE PRESENCE OF AN OXIDATION CATALYST SELECTED FROM THE CLASS CONSISTING OF THE OXIDES AND SALTS OF THE METALS OF GROUPS V AND VIII, INCLUSIVE, OF THE PERIODIC TABLE; AND RECOVERING PYROMELLITIC ANHYDRIDE FROM THE CRUDE OXIDATION PRODUCT.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-06-16 | 1967-12-16 | 1968-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-06-16 | 1971-12-16 | 1972-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-06-16 | 1975-12-16 | 1976-06-16 | $7700.00 | Window Closed / Lapsed |