Methyl Orange Degradation Using Ag-Doped TiO₂, H₂O₂, and Hydrodynamic Cavitation

Area of Science:

• Environmental Chemistry
• Materials Science
• Chemical Engineering

Background:

• Methyl Orange (MO) is a common industrial pollutant requiring efficient degradation methods.
• Photocatalysis offers a promising route for pollutant degradation, but efficiency can be limited.
• Doping titanium dioxide (TiO2) with silver (Ag) can enhance its photocatalytic activity.

Purpose of the Study:

• To synthesize and characterize Ag-TiO2 photocatalysts with varying silver concentrations.
• To investigate the photocatalytic degradation of MO using optimized Ag-TiO2.
• To explore synergistic effects of combining photocatalysis with hydrogen peroxide and hydrodynamic cavitation for enhanced MO degradation.

Main Methods:

• Ag-TiO2 photocatalysts were synthesized using a solid-state method with 0-2.5% Ag.
• Characterization included XRD, SEM-EDS, and BET analysis.
• Photocatalytic degradation experiments were conducted under varying UV light intensities, catalyst loadings, and combined advanced oxidation processes (AOPs).

Main Results:

• 0.5% Ag-TiO2 showed optimal performance, achieving 59% MO degradation under 200 W UV light.
• Combining photocatalysis with 0.01% H2O2 enhanced degradation to 94% with a synergistic coefficient of 24.
• The triple combination of photocatalysis, H2O2, and hydrodynamic cavitation achieved complete MO degradation in 3 minutes with a synergistic coefficient of 42.

Conclusions:

• Optimized Ag-TiO2 composition and operational parameters significantly enhance MO degradation.
• Synergistic effects in advanced oxidation processes, particularly with hydrodynamic cavitation, are highly effective for rapid pollutant removal.
• The study highlights the potential of combined AOPs for efficient wastewater treatment.