METHOD FOR PREPARING TEREPHTHALIC ACID

摘要

PURPOSE: A method for preparing a terephthalic acid is provided to remove a reaction intermediate effectively and to improve the yield and quality of the final terephthalic acid by making solid crude terephthalic acid having a plurality of intermediates to be slurry and then oxidizing it. CONSTITUTION: A method for preparing a terephthalic acid comprises the steps of (a) mixing a solid crude terephthalic acid containing at least one intermediate between para-toluic acid and 4-carboxybenzaldehyde to form a slurry; and (b) oxidizing the slurry with the terephthalic acid in the presence of a first catalyst system containing at least one kind selected from a cobalt precursor and manganese precursor or a second catalyst system containing the cobalt precursor and manganese precursor.