Synthesis of TiO2/g-C3N4 Photocatalyst with Recovered TiO2 from Spent SCR Catalyst for Photodegrading Rhodamine B

摘要

Abstract Purpose TiO2 recovered from spent SCR catalyst, a hazardous industrial solid waste, was modified by g-C3N4 to produce the recovered TiO2 (R-TiO2)/g-C3N4 photocatalyst to protect valuable Ti resources and revamp its shortage of underutilization of visible light.Methods TiO2 recovered from spent SCR catalyst by an alkali leaching method was used to prepare the R-TiO2/g-C3N4 photocatalyst via self-assembly procedure. The photodegradation efficiencies of the prepared catalysts were evaluated by degradation of Rhodamine B (RhB) under visible light.Results The XRD patterns indicate that R-TiO2 remains the crystal structure of the standard anatase TiO2 phase intact throughout the recovery process. The photodegradation efficiencies of the R-TiO2/g-C3N4 photocatalysts evaluated by degradation of RhB under visible light optimally reached 97.11% when the systems were irradiated for only 40?min. For comparison, the best RhB degradation rate constant from the R-TiO2/g-C3N4 photocatalyst was about 1.9 times that of the pure TiO2/g-C3N4 photocatalyst.Conclusion The R-TiO2/g-C3N4 photocatalyst with the 97.616 wt% purity R-TiO2 has the highest visible light photocatalytic degradation RhB activity which is almost 1.9 times that of pure TiO2/g-C3N4 photocatalysts. The results demonstrate that the TiO2/g-C3N4 photocatalyst with recovered TiO2 from spent SCR catalyst shows excellent photodegradation efficiency for RhB.Graphical abstract