Process for recovering the mother liquor produced by the esterification of terephthalic acid with methanol
US4005124A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 20, 1974 |
| Grant date | Jan 25, 1977 |
| Priority date | — |
| Expiry date | Nov 20, 1994 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C67/56
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The process of recovering methanolic mother liquor obtained by the esterification of terephthalic acid with methanol, where the terephthalic acid may be unprepurified, is improved by adjusting to a specific gravity of about 0.85 - 0.98 by addition of water and/or methanol distillate, a mother liquor containing esterification water and dissolved solids at a concentration of about 1.0 to 6.0 percent by weight and cooling the mother liquor from a temperature of about 65.degree. - 85.degree. C to a temperature of about 10.degree. - 30.degree. C to separate the solids and remove the separated solids. The separated solids may be recycled into the esterification reaction and the unseparated solids may be recycled for oxidation to terephthalic acid following distillation to remove the methanol.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.