| Predicate |
Object |
| assignee |
http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_bcd600c789c13101f39db5af4f289a97 |
| classificationCPCInventive |
http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07C51-09 |
| classificationIPCInventive |
http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07C27-02
http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07C51-00
http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07C51-09
http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07C63-26
http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07C69-82
http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07C67-00 |
| filingDate |
1979-09-27-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| grantDate |
1981-11-24-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| inventor |
http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_c8c9364c8596c497774145f00dfd6934
http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_49fa8d83f38b82216ee76f2dbbe69cd9
http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_3708a97b3933c994b57c2fa7ecacfbae |
| publicationDate |
1981-11-24-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber |
US-4302595-A |
| titleOfInvention |
Process for the preparation of terephthalic acid by the hydrolysis of intermediate stage crude dimethyl terephthalate |
| abstract |
In a process for the preparation of fiber-grade terephthalic acid from intermediate stage crude dimethyl terephthalate, the crude dimethyl terephthalate, which has a limited content of intermediate oxidation products including a content of terephthalaldehydic acid methyl ester of up to 0.1% by weight based on the weight of the crude dimethyl terephthalate, is hydrolyzed with water at a weight ratio of the crude dimethyl terephthalate to water of between 3:1 and 0.1:1 and at a temperature between 140° C. and 350° C. and under a pressure required to maintain a liquid phase (e.g., from 6 to 200 bars) to produce a reaction mixture containing crystalline fiber-grade terephtalic acid and thereafter the terephthalic acid is recovered from the reaction mixture. The initial crude dimethyl terephthalate used as a starting material is obtained from a crude ester mixture produced by the oxidation of p-xylene and/or methyl p-toluate with oxygen-containing gases in the presence of heavy metal-containing oxidation catalyst at an elevated temperature and under an elevated pressure and by esterification of the oxidation mixture with methanol at an elevated temperature and elevated pressure followed by separating the resulting crude ester mixture by distillation into a methyl p-toluate enriched fraction, a residual high-boiling fraction and the crude dimethyl terephthalate having the limited content of intermediate oxidation products. |
| isCitedBy |
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-4578501-A
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-10752776-B2
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-2010298524-A1
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-5563294-A
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-5679848-A
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-6472557-B1
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-5728870-A
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/KR-100276934-B1
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/WO-9312065-A1
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-4642377-A
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-11535581-B2
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/WO-0047658-A1
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/WO-2010148049-A2
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/WO-2010148070-A2
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/WO-2010148063-A2
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/WO-2010148081-A2
http://rdf.ncbi.nlm.nih.gov/pubchem/patent/WO-2010148080-A2 |
| priorityDate |
1979-04-21-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type |
http://data.epo.org/linked-data/def/patent/Publication |