Porous TiO2 with large surface area is an efficient catalyst carrier for the recovery of wastewater containing an ultrahigh concentration of dye

The preparation of porous TiO2 as a carrier for the Fenton reaction is reported. Porous TiO2 is an excellent carrier to load with elemental iron due to the large specific surface area and negative surface charge. Porous TiO2 was synthesized in the form of a hierarchically porous silica monolith that was used as a microreactor, and a block copolymer served as a template for mesoporous forms. The crystalline TiO2 growing in confined spaces maintained the porous structure and high crystallinity. The surface area of our synthesized porous TiO2 can reach 205 m(2) g(-1). The zeta potential of the TiO2 was as low as -36.5 mV (pH 7). Elemental iron was highly and uniformly dispersed over the channel of the porous TiO2 via an impregnation method and served as the catalyst for the Fenton reaction. In the Fenton reaction, the synthesized catalyst performed strong catalytic activity during the degradation of wastewater containing an ultrahigh concentration of aqueous dye, at 400 ppm. The aqueous dye solution was degraded over 95% in 30 min, and the catalyst could be reused many times.