A novel high-performance CeO₂-CuMn₂O₄ catalyst for toluene degradation

A series of spinel CuM₂O₄ (M = Mn, Fe, and Al) was used as the catalyst to investigate the effective degradation of toluene, and then CuMn₂O₄ with better catalytic activity was selected as the research object to study its activity at different ratios of Cu and Mn. Meanwhile, CeO₂ was introduced to modify CuMn bimetallic oxide to improve its catalytic performance. The structure, morphology, and valence states of surface elements of as-prepared catalysts were characterized by XRD, TEM, SEM, N₂ adsorption-desorption, XPS, and H₂-TPR. Using toluene as a probe molecule, the catalytic activity of the catalyst was tested and the results showed that the conversion rate of toluene catalyzed by CeO₂-CuMn₂O₄ catalyst can reach 90% at 200 °C (T₉₀) and 100% at 240 °C (T₁₀₀). The CO₂ yield can also reach 100% at 248 °C. Moreover, the possible catalytic mechanism for toluene by the CeO₂-CuMn₂O₄ was briefly explored. The catalytic oxidation of toluene over the oxide follows the Mars-van Krevelen mechanism.