Process for the purification of terephthalic acid
US4340752A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 21, 1978 |
| Grant date | Jul 20, 1982 |
| Priority date | — |
| Expiry date | Mar 21, 1998 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C51/487
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for the purification of terephthalic acid in which a dispersion of the terephthalic acid in a liquid dispersant such as acetic acid is continuously pumped repeatedly through a cycle. Fresh dispersion is fed continuously into the cycle while simultaneously a corresponding amount of treated dispersion is removed. The cycle comprises a heater and a cooler and the cooler serves as a crystallizer. The dispersion prior to entering the heater is subjected to a highly effective particle comminution and is exposed upstream of or in the heater to an oxygen containing gas such as air. The acetic acid dispersant is removed from the treated dispersion and recycled to the cycle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.