Process for preparing terephthalic acid by the catalytic oxidation with air of p-xylene in a water containing acetic acid solvent
US4593122A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 27, 1984 |
| Grant date | Jun 3, 1986 |
| Priority date | — |
| Expiry date | Jul 27, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/52
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for producing terephthalic acid from p-xylene continuously, wherein p-xylene is oxidized to terephthalic acid by air in the presence of a catalyst containing cobalt, manganese and bromine at a temperature of 180.degree. to 230.degree. C. in a water containing acetic acid solvent in which the concentration of oxygen gas contained in an exhaust gas obtained from the reaction vessel used for oxidizing p-xylene is 2 to 8% by volume, said process comprising, (a) preparing an oxidation exhaust gas by condensing a gas withdrawn from said reaction vessel for removing condensates from said gas, (b) dividing the prepared oxidation exhaust gas into a discharged gas and a recycled gas, in which the volume ratio of said recycled gas to said discharged gas is 0.3 to 5, said discharged gas being exhausted to the outside of the reaction system, (c) supplying continuously said recycled gas to the liquid phase of said reaction vessel, and (d) carrying out the oxidation reaction of p-xylene under reaction pressure higher than the pressure of the reaction system when gas is not recycled to the system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.