Removal of persistent tartrazine dye by photodegradation on TiO₂ nanoparticles enhanced by immobilized calcinated sewage sludge under visible light

ABSTRACT

TiO₂ nanoparticles on calcined sewage sludge (TiO₂/sludge) were prepared by the sol-gel method and were fully characterized. The photocatalytic efficiency of TiO₂/sludge was evaluated by tartrazine dye degradation by halide lamp. TiO₂/sludge exhibited a high photocatalytic oxidation efficiency (more than 90%) of tartrazine compared with naked TiO₂ (less than 20%) due to the synergy effect of sewage sludge. The optimization of experimental conditions was 0.5 g/l TiO₂/Sludge, pH 8 with 50 mg/l tartrazine dye. The addition of sewage sludge to TiO₂ improves the efficiency of dye mineralization. The prepared catalyst showed easier separation and effective reuse.

KEYWORDS:

• TiO₂/sludge
• tartrazine dye
• visible light
• degradation
• photocatalysis
• reuse