Patent · US Expired

Method of recovering in active form the catalyst for the terephthalic acid synthesis

US4356319A · kind A · utility

117Cited by
4References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 19, 1981
Grant dateOct 26, 1982
Priority date
Expiry dateJan 19, 2001

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P20/584
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A method of recovering the catalyst in active form from the acetic mother liquors from the synthesis of terephthalic acid. From said mother liquors, after removal of water, there is removed by evaporation an amount of from 70 to 90% of the CH.sub.3 COOH present therein. The concentrated liquor is cooled below 60.degree. C. and the solid which precipitates is collected and recycled for reuse in the systhesis. The liquid phase is extracted with water or with an aqueous acetic acid solution in the presence of particular coadjuvants such as isobutyl acetate, and the aqueous phase, which contains the recovered catalyst, is recycled to the original synthesis.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.