| 摘要 |
PURPOSE:To obtain the titled compound in high purity, suppressing the production of nucleus-brominated material, by oxidizing 2,6-diisopropylnaphthalene in a lower aliphatic monocarboxylic acid solvent having a water-content falling within a specific range in the presence of a catalyst containing Co, Mn and extremely small amount of bromine. CONSTITUTION:2,6-Diisopropylnaphthalene is oxidized with molecular oxygen in a lower aliphatic monocarboxylic acid (preferably acetic acid) having a water-content of <=30wt%, especially <=15wt% in the presence of a catalyst containing Co and/or Mn and Br and the reaction mixture is cooled to separate the titled compound as a solid. The atomic ratio of Br to the heavy metal component in the catalyst is >=0.0001 and <0.01, preferably 0.0005-0.008. The separated mixture is added to an aqueous solution of a mineral acid to decrease the pH to <=3 and the precipitated isoluble 2,6-naphthalenedicarboxylic acid is separated by filtration. The filtrate is concentrated while keeping the pH at <=3 and cooled to crystallize trimellitic acid, which is separated from the liquid by filtration. The filtrate is added with an alkali metal (bi)carbonate and the heavy metal is recovered as a (basic) carbonate.
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