Patent · US Expired

Process for the production of fiber-grade terephthalic acid

US4158738A · kind A · utility

129Cited by
4References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 26, 1977
Grant dateJun 19, 1979
Priority date
Expiry dateMay 26, 1997

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P20/52
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

Process for the preparation of fiber-grade terephthalic acid by continuously oxidizing paraxylene while vaporizing a portion of the contents of the reactor. Fiber-grade terephthalic acid is produced by maintaining (1) a temperature of at least 210.degree. C., (2) a molecular oxygen content of the noncondensables in the vapor withdrawn from the reactor in the range 3.0-6.0%, (3) a water level of the contents of the oxidizer in the range 5.0-17.0%, (4) a mole ratio of sodium to cobalt plus manganese in the range 0.06-2.0 in the reactor, (5) a mole ratio of cobalt to manganese in the range 0.5-5.0 (6) an organic burn in the range 8.0-15.0 burn units and (7) a productivity in the range 0.45-1.45 pounds of terephthalic acid per minute per 100 pounds of reactor contents.

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