Process for producing terephthalic acid
AssigneeMitsubishi Chemical Industries Limited
InventorsTsuneo Kimura, Hiroshi Hashizume, Yoshiaki Izumisawa
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Abstract
There is disclosed a process for producing terephthalic acid in which the reaction temperature range and the proportion of catalyst components of a cobalt compound, a manganese compound and at least one bromine compound are specifically chosen to produce a high grade terephthalic acid suitable for direct polycondensation in the production of polyester.
Claims7
In a process for the production of terephthalic acid comprising oxidizing p-xylene in an acetic acid solvent with an oxygen-containing gas in the presence of a catalyst, the improvement which comprises the reaction temperature being from 205.degree. C to 225.degree. C, and said catalyst consisting essentially of
- a. a cobalt compound containing 200 to 600 parts of cobalt per million parts of said solvent,
- b. a manganese compound containing 0.5 to 1.5 times the weight of said cobalt of manganese, and
- c. a bromine compound taken from the class consisting of hydrogen bromide, manganese bromide, and cobalt bromide, said bromine compound comprising 400 to 2000 parts of bromine per million parts of said solvent.
Dependencies are inferred from the claim text.