The Effect of Hydrogen Peroxide on Catalytic Activity of Manganosite MnO/Oil Palm Fly Ash Catalyst for Degradation Methylene Blue

Dye pollutions have become a major environmental problem due their mutagenic, carcinogenic nature, toxicity and stability. The effective removal of this recalcitrant material from wastewater requires immediate solution. The Fenton-based advanced oxidation processes have been considered as highly effective and efficient method for the degradation of highly stable organic contaminants. In this work, the composite MnO/oil palm fly ash (OPFA) was first synthesized, characterized and applied as a heterogeneous Fenton catalyst for the degradation of methylene blue (MB). The composite was characterized by X-ray powder diffraction (XRD), and Brunauer–Emmett–Teller (BET). The XRD result indicated that the manganese oxide phase in the composite is the rock-salt manganese oxide of manganosite MnO. The MnO/OPFA has a surface area of 278.541 m²/g, which is much higher than those of pure manganosite or OPFA. The catalytic test indicated that the concentration of hydrogen peroxide (H₂O₂) seems to play a significant role for the effective degradation of MB. The degradation of MB was 95.31 achieved only within 10 minutes of reaction time with the addition of 5 ml of H₂O₂, 125 mg catalyst using 100 ml 12.5 ppm MB.