Abstract

New simple wet-ultrasonic method was employed to synthesize akind of particle heterogeneous catalyst Fe₃O₄/attapulgite (Fe₃O₄/ATP), which used attapulgite particles as catalyst carrier and Fe₃O₄ as active component loaded on the carrier. The catalyst is low cost and easy to prepare, and the effects of various preparing factors on its catalytic performance were investigated and discussed. The heterogeneous catalyst was characterized using SEM, FT-IR and XRD for its structure and catalysis properties. Fe3O4/ATP was used as the catalyst to decolorize high concentration (100mg/L) methylene blue (MB) in the heterogeneous Fenton system. Box-Behnken design (BBD) method was used for experimental design, data analysis and optimization. The influences of catalyst dosage, H₂O₂ initial concentration and pH value on MB decolorization ratios in Fe₃O₄/ATP/H₂O₂ heterogeneous Fenton system were studied. The heterogeneous catalyst Fe₃O₄/ATP has excellent catalytic performance and more than 99%MB decolorization were achieved under the optimum conditions. Higher decolorization ratio was obtained for recycled use of Fe₃O₄/ATP. Comparison experiments showed MB decolorization in Fe₃O₄/ATP/H₂O₂ system is really a catalytic process. Furthermore, Fe3O4/ATP can be easily separated from the solution and reused due to its particle form.