Keywords: catalytic wet oxidation, NaY zeolite, coal fly ash, azo dye, Acid Orange 7, wet peroxide oxidation, dye removal, colour removal, COD removal, chemical oxygen demand
Catalytic wet peroxide oxidation of azo dye (Acid Orange 7) using NaY zeolite from coal fly ash
This work concerns the synthesis of NaY zeolite derived from low–cost materials like fly ash (FA) for degradation of Acid Orange 7 (AO7) by catalytic wet peroxide oxidation. Synthesised NaY zeolite is characterised using XRD, SEM/EDAX and FTIR. The results indicate that synthesised NaY zeolite is a promising catalyst for dye removal. The effects of various operating parameters like temperature, initial pH, hydrogen peroxide concentration and catalyst loading on the removal of dye, colour and COD from an aqueous solution were studied at atmospheric pressure. The percent removals of dye, colour and COD at optimum pH0 2, 90°C using 0.6 ml H2O2 solution and 1.5 g/l catalyst was 97% (in 4 h), 99.8% (in 45 min) and 70% (in 4 h), respectively. The % dye removal has been found to be less in comparison to % colour removal at all conditions, e.g., dye removal in 45 min and at above conditions was 82%, whereas the colour removal was 99.8%. Dye, colour and COD removals were maximum at pH0 2.