Metal‐Ion and UVC Light‐Catalyzed Oxidation and Biodetoxification of Ponceau Xylidine in Aqueous Solution: A Comparative Study

Metal ion ( /oxidant) and UV light catalyzed (UV/oxidant) mineralization and biodetoxification of Ponceau Xylidine (PX) was undertaken in this study. Hydrogen peroxide (HP) and ammonium persulphate (APS) were employed as oxidants and and as metal ion catalysts. Although highest mineralization in /APS and UV/HP systems was exhibited at pH 1 (63.09 %) and 3 (64.83 %), respectively, lowest was shown by /oxidant systems at any pH. The Fenton process achieved mineralization of ≈48.50 % within the pH range of 3 to 6.15. The study established as a better catalyst than , and HP, a better oxidant (2.5 times more effective) than APS. Mineralization with UV/HP at 120 min is highest at pH 3 (92.0 %) and 6.15 (86.17 %). Various inorganic anions were found to inhibit mineralization. The maximum and minimum inhibition was shown by in UV/HP and UV/APS systems respectively. The inhibition effect of decreases with concentration till 0.01 mM, beyond which an increasing trend was observed. This study also demonstrates that the biodetoxification efficiency of various systems is in the order: UV/HP>UV/APS> /HP. Thus, UV/HP is the most suitable system for the treatment of PX, displaying a biodetoxification efficiency of 83.0 % and mineralization of 92.0 %.