| 摘要 |
PURPOSE:To provide an efficient production method of naphthalenedicarboxylic acid by circulatively reusing an oxidation reaction catalyst, continuously oxidizing dimethylnaphthalene. CONSTITUTION:In oxidizing dimethylnaphthalene and/or its oxidation derivative with a molecular oxygen-containing gas in a solvent containing at least twice as much as a lower aliphatic carboxylic acid (preferably acetic acid) by weight, having 5-45wt.%, especially 10-30wt.% water content in the presence of an oxidation catalyst composed of a heavy metal, preferably cobalt, manganese and bromine, the catalyst is supplied in such a way that the effective concentration of the heavy metal catalyst prepared by removing o-benzenedicarboxylic acid complex of heavy metal contained in the solvent is made >=0.2wt.%, preferably 0.4-1.0wt.% and almost the whole amount of the reaction mother liquor and/or formed cake is circulated and reused. |
