Porous Solid Superacid SO42-/Fe2-xZrxO3 Fenton Catalyst for Highly Effective Oxidation of X-3B under Visible Light

Porous solid superacid SO42-/Fe2-xZrxO3 bimetallic oxide was first synthesized by citric acid templated method and impregnated in vitriol solution. The prepared catalyst possessing mesopores and macropores exhibited high activity for degradation of azo dye in photo-Fenton reaction under visible-light irradiation. By characterization of the catalysts, it revealed that both Bronsted and Lewis acid sites immobilized on solid surface were attributed to the synergetic effect of Zr and SO42-. The kinetic courses of dye adsorption and catalytic peroxide oxidation were discussed. A combined first-order kinetics model well fitted for photo-Fenton degradation indicated that both the unique surface acid property of solid and visible-light induced electron transfer enhanced catalytic performance. The strong acid sites were the key factor in widening the working pH range to 10.0 and determining the activity of catalysts, which were proved by a high removal rate up to 98% of X-3B even in dark Fenton process.