Green SBA-15 as a Fenton Catalytic Support for Efficient Degradation of Indigo Carmine

Green mesoporous SBA-15 was synthesized by using corn stack ash (CSA), a new renewable silica source, as the main raw material. 80 wt% sodium silicate solution from CSA was mixed with a tetraethyl orthosilicate (TEOS) solution, and fi nally after a hydrothermal process, mesoporous SBA- 15 was obtained. Subsequently, iron metal was incorporated into the prepared SBA-15 and used as an effi cient Fenton catalyst for degradation of indigo carmine (IC) under various conditions. Effects of various parameters of the Fenton process: initial pH, H2O2 concentration, Fe content, and reaction temperature were studied. It was observed that Fe2O3/80CSBA demonstrated good activity not only for a wide range of pH (both of acidic and basic conditions), but also at room temperature. Using the optimum condition, 98% of IC removal can be reached within 10 min. Moreover, the catalyst exhibited long-term stability and strong resistance to leaching of Fe species, while incorporating metal only 0.5 wt% of metal.