Synthesis, Characterization Of Co₃O₄ /Al₂O₃ Nanomaterials And Catalytic Degradation On Rhodamine B

Cobaltosic oxide with the spinel phase has great application in treatment of dye-containing wastewater by catalytic degradation. Micro- or nano-aluminum oxide has been extensively used as catalyst supports due to its high chemical stability, high thermal stability, and high specific surface area.By hydrothermal synthesis method, using surfactants natural soybean lecithin and cetyltrimethyammonium bromide as templates, cobaltosic oxide spherical nanostructures and alumina nanoparticles were prepared. The supported type catalysts cobaltosic oxide/aluminum oxide was also synthesized by high temperature solid phase reaction. The as-prepared products were characterized by X-ray powder diffraction (XRD), ultraviolet–visible spectrum, field-emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FT-IR). The main results are as follows:1. Cobaltosic oxide spherical nanostructures were fabricated via a hydrothermal process using lecithin spherical micelle as template and cobalt acetate tetrahydrate as precursors. Micelle templates were formed by ultrasonic and intensive magnetic stirring under assisted solvent absolute alcohol. The influences of alcohol dosage, temperature, reaction time and alkaline source on morphology of products were researched, and a possible formation mechanism of cobaltosic oxide spherical nanostructures was discussed.2. AlOOH nanoparticles were synthesized by hydrothermal process at 200 oC for 12 h, using aluminum nitrate, triethylamine as precusors and cetyltrimethyammonium bromide as template. On this basis, the alumina support was prepared by high temperature solid state reaction using the as-synthesized AlOOH nanoparticles as precursor at 520oC for 3h. The catalytic degradation of Rhodamine B by supported catalyst Co₃O₄/Al₂O₃ and influences of loading, pH of initial solution, and concentration of Rhodamine B on the catalytic efficiency were studied. And the catalytic performance of cobalt oxide/alumina composite with other different kinds of metal oxides alumina composites was also compared. The results showed that when the loading of Co₃O₄ was 1/3, Rhodamine B concentration was 5mg / L, Rhodamine B solution pH was 2, the degradation rate was the highest in the Co₃O₄/Al₂O₃ system. However, V2O5/Al₂O₃, similar to MnO2/Al₂O₃, on the catalytic degradation of Rhodamine B is better than Co₃O₄/Al₂O₃ under the same conditions. These results lay the basis for further study of similar catalysts.