Preparation of Terephthalic Acid from Coal Acids Using Slurry System

摘要

This paper relates to a method to produce terephthalic acid (TPA) by the isomerization of the dry potassium coal acids salts from coal acids produced coal oxidation using a catalyst Zn(Bzo)2 in slurry bed. Effects of dispersant content,initial CO2 pressure, content of catalyst and temperature were investigated. It was confirmed that coal acids can be converted to TPA in the presence of the catalyst using biphenyl or p-terphenyl as dispersant in slurry system. The optimum conditions of isomerization were found to be: amount of the dispersant is 60%, initial CO2 pressure >1.0MPa, catalyst content 3%; isomerization temperature is 380 °C for p-terphenyl as dispersant and 420 °C for biphenyl as dispersant.