Patent ID: 6310239
Filing Date: 2001-10-30
Classification: C07C

Abstract:
A process for manufacturing terephthalic acid from alkali weight reduction waste water, comprising:separating dialkali terephthalic acid from impurities to produce a separated aqueous solution comprising dialkali terephthalic acid, said separating comprising adsorbing said alkali weight reduction waste water onto a filling material, wherein said alkali weight reduction water has a pH above the first equivalence point of terephthalic acid and comprises dialkali terephthalic acid; and thereafter:neutralizing said separated aqueous solution which comprises dialkali terephthalic acid with acid to produce terephthalic acid;crystallizing said terephthalic acid to enlarge the particle size of the crystals of terephthalic acid;cooling said enlarged crystals of terephthalic acid;filtering said enlarged crystals of terephthalic acid; anddrying said enlarged crystals of terephthalic acid.