Adsorptive Separation and Recovery of Organic Compounds from Purified Terephthalic Acid Plant Effluent.

Several organic impurities formed in the p-xylene oxidation process for manufacture of terephthalic acid are carried into the aqueous effluent from the crystallization section of PTA plant of crystallizers for purified terephthalic acid (PTA). These compounds impose a burden on the effluent treatment plant. Due to the presence of these impurities the recycle of aqueous effluent from crystallization section of PTA plant to the PTA crystallizer is not possible. The aim of this study is to check the feasibility of removal of these organic impurities from the aqueous effluent from crystallization section of PTA plant by adsorption on polymeric resins so that the aqueous effluent from crystallization section of PTA plant can be recycled resulting in significant saving of process water. Aqueous effluent from crystallization section of PTA plant was characterized and single solute and multisolute adsorption equilibria of the compounds present were determined for a variety of polymeric adsorbents. Column breakthrough study has shown that the components can be removed and recovered from the aqueous effluent from the crystallization section of PTA plant by adsorption. [ABSTRACT FROM AUTHOR]