PRODUCTION OF DIALKALI METAL SALT OF NAPHTHALENE-2,6-DICARBOXYLIC ACID

摘要

PURPOSE:To effectively and economically obtain the subject substance in short time by heating naphthalene dicarboxylic acid dialkali metal salt at specific temperature range in the presence of catalyst and under pressure of CO2, then heating at a temperature higher than the above temperature. CONSTITUTION:Naphthalene dicarboxylic acid dialkali metal salt is heated at first stage to 320-420 deg.C (preferably 350-410 deg.C) with a temperature rising speed exceeding of 40 deg.C for every minute in the presence of catalyst (e.g., Cd, Zn or Hg compound) and under pressure of CO2. The salt is kept at said temperature for >=5 min (preferably 10-60min) and then heated at a temperature 10 deg.C higher than the temperature of the first heating within a range of 410-500 deg.C (preferably 420-460 deg.C) and transformed to the subject substance. A substance of liquid in the reacting condition and having good stability may be used as dispersing medium or solvent and non-protonic polycyclic aromatic compound (e.g., naphthalene) is shown as an example.