Photocatalytic Degradation of Acid Chrome Blue K with Porphyrin-Sensitized TiO₂ under Visible Light

We have investigated an application of TiO 2 photocatalyst sensitized with meso-tetra (4-carboxyphenyl) porphyrin (H 2 TPPC) or meso-tetra (4-nitrophenyl) porphyrin (TNO 2 PP) to degrade acid chrome blue K (ACBK) under visible light irradiation. By injecting electrons from the photoexcited sensitizer to the conduction band, the sensitized TiO 2 degraded acid chrome blue K under incandescent lamp irradiation. The results indicated that H 2 TPPC−TiO 2 had remarkable effects on the photodegradation of ACBK under natural sunlight (NSL) irradiation. The initial concentration of ACBK of 10 mg/L gave the decolorization rate of ACBK under incandescent lamp irradiation up to 94% in 15 min. This confirms that the H 2 TPPC−TiO 2 composite could fully decompose ACBK under artificial light and that this process was accelerated under NSL. All facts suggest that H 2 TPPC−TiO 2 in the heterogeneous photocatalysis phase has a potential application in wastewater treatment by using NSL.