Method for preparing 2,5-dihydroxy p-benzene dicarboxylic acid

Abstract

A method for the carboxylation preparation of 2,5-dihydroxyterephthalic acid by taking n-octane as solvent to Pd(II) / C-catalyze the hydroquinone is disclosed, specifically comprising the steps of: in a high-pressure reaction kettle, taking sodium phenolate, potassium hydroxide and carbon dioxide as reactants, performing Pd(II) / C-catalysis to prepare 2,5-dihydroxyterephthalic acid sylvite, and obtaining the 2,5-dihydroxyterephthalic acid by means of recrystallization and acidification. The inventive catalyst is simply prepared, the solvent is easy for recovery and the product is high in purity.

Description

technical field

[0001] The invention relates to a method for catalytically preparing 2,5-dihydroxyterephthalic acid, specifically referring to using n-octane as a solvent and using Pd(II) / C as a catalyst to catalyze hydroquinone, potassium hydroxide and carbon dioxide After oxidation reaction, 2,5-dihydroxyterephthalic acid is prepared by acidification. Background technique

[0002] 2,5-Dihydroxyterephthalic acid is an important intermediate in organic synthesis, which can be used to synthesize polymers, complexes, colorants and fluorescent substances. The mixture of 2,5-dihydroxyterephthalic acid and terephthalic acid can be reacted with ethylene glycol to produce shaped polyester or copolyether with fiber and film-forming properties. 2,5-diamino-1,4-benzenedithiol undergoes non-homopolymerization in polyphosphoric acid to generate high-molecular-weight linear polyesters and copolymers, and 2,3,5,6-tetraaminopyridine (TAP) It can be directly polymerized into M5 polymer wi...