IN-SITU Dual Effect Studies for the Degradation of Phenazone Using Slurry and Fixed Bed Approach

Abstract

The present study deals with heterogeneous photocatalytic, photo-Fenton and in-situ dual process for the degradation of Phenazone in slurry and fixed-bed using TiO2 and waste foundry sand. The degradation rate followed the first order rate kinetics with optimized condition for the photocatalytic degradation of Phenazone TiO2 0.375g/L, H2O2 0.075g/L, C0 50mg/L at pH 5 with the wavelength 244 nm. Approximately 94% reduction in the concentration of compound was observed after 3 hours. Present study focuses on use of foundry sand as an iron source for the photo-Fenton treatment of Phenazone. Experiment was performed in UV light to check the efficiency of the process. The degradation rate was observed to follow first-order kinetics Foundary sand 1.0g/L, pH 3, H2O2 0.450g/L were optimized conditions for obtaining the better degradation rates. Approximately 93% reduction in the concentration of Phenazone was observed after 180 min. In-situ dual treatment for the degradation of Phenazone was also carried out at optimized conditions for slurry mode in sunlight TiO2 0.375g/L, H2O2 0.450g/L at pH 3. The percentage degradation of Phenazone in natural sunlight as 95% was achieved in 90 min. The dual treatment is also carried out in Fixed-bed reactor at optimised conditions H2O2 1.350g/L at pH 3 with 96% reduction in the concentration of Phenazone was observed after 4 hours. The COD reduction (75%) along with the generation of nitrite, nitrate confirmed the complete mineralization of the selected compound. Fixed-bed studies were also carried out with TiO2 on Clay/F.S. disc which eliminates the implication of slurry mode photocatalysis. The recyclability of catalyst was confirmed by recycling the disc for at least 10 cycles and characterized by the SEM/EDAX. Therefore, the technique visualized in this study by employing renewable energy and durable catalyst can provide a viable solution to the industries for treating biorecalcitrant compounds.