Gold catalysts supported on cerium-modified mesoporous zirconia for total toluene oxidation. Effect of Ce/Zr molar ratio
Résumé
Our study focused on the synthesis of gold catalysts supported on mixed Ce–ZrO2 (Ce/Zr = 0, 0.1, 0.4 and 0.9) mesoporous, which are mainly potential in the total oxidation of toluene and other volatile organic compounds. The mesoporous Ce–ZrO2 oxides (Ce/Zr = 0, 0.1, 0.4 and 0.9) were prepared via soft template strategy, using a triblock copolymer as a template. 1% of Au was loaded on mixed oxide mesoporous by deposition precipitation method. Ce–ZrO2 and Au/Ce–ZrO2 (Ce/Zr = 0, 0.1, 0.4 and 0.9) samples were characterized by XRD, N2 adsorption–desorption, H2-TPR and MET. The results showed that the dispersion of the gold particles on Ce–ZrO2 depends on the Ce/Zr ratio. These catalysts were then tested in the deep oxidation of toluene oxidation where they exhibited an excellent catalytic activity by complete decomposition of toluene at the reaction temperature equal to 576 K. This activity is correlated with the dispersion of the gold particles; itself is correlated with the Ce/Zr ratio.