| abstract |
Terephthalic acid is produced by oxidizing, in a liquid phase, p-tolualdehyde with a gas containing molecular oxygen, for example, air, in the presence of a catalyst consisting each of (1) a manganese compound, (2) a cobalt compound, (3) a bromine compound, and (4) at least one compound selected from the group consisting of chromium compounds, iron compounds, nickel compounds and compounds of metallic elements belonging to the lanthanide series, using a lower aliphatic monocarboxylic acid as a solvent. |