Cerium–Copper–Manganese Oxides Synthesized via Solution Combustion Synthesis (SCS) for Total Oxidation of VOCs

• Published in: Catalysis letters Vol. 150; no. 6; pp. 1821 - 1840
• Main Authors: Marin Figueredo, Miguel Jose, Andana, Tahrizi, Bensaid, Samir, Dosa, Melodj, Fino, Debora, Russo, Nunzio, Piumetti, Marco
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.06.2020; Springer; Springer Nature B.V
• Subjects: Catalysis; Catalysts; Catalytic activity; Cerium; Cerium oxides; Chemistry; Chemistry and Materials Science; Combustion; Combustion synthesis; Copper; Copper oxides; Diffraction; Ethylene; Industrial Chemistry/Chemical Engineering; Manganese; Monolithic materials; Organometallic Chemistry; Oxidation; Oxides; Photoelectrons; Physical Chemistry; Propylene; X ray photoelectron spectroscopy; X-ray spectroscopy; X-rays; Cerium oxide-based catalysts; Catalytic oxidation of VOCs; Solution combustion synthesis; Monolithic catalyst; Redox-type mechanism
• ISSN: 1011-372X; 1572-879X
• DOI: 10.1007/s10562-019-03094-x

A set of cerium–manganese–copper oxide catalysts with various foreign metal contents was prepared via the solution combustion synthesis (SCS). The catalysts were characterized by complementary techniques such as N 2 physisorption at − 196 °C, X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), H 2 -temperature-programmed reduction (H 2 -TPR), O 2 -temperature-programmed desorption (O 2 -TPD) and X-ray photoelectron spectroscopy (XPS). Their catalytic activity was tested towards the VOC oxidation using ethylene and propylene as probe molecules. As a whole, it has been observed that the Ce 55 Mn 45 sample (Mn 45 at.%), containing MnO x clusters interacting with the ceria phase, was the most active catalyst for propylene oxidation, exhibiting a complete conversion at 250 °C. On the other hand, the ternary oxide catalyst (Ce 55 Mn 22.5 Cu 22.5 with Mn = 22.5 at.% and Cu = 22.5 at.%) has exhibited the best results for the oxidation of ethylene. These findings suggest that the co-presence of different active phases on the catalytic surface may have a beneficial (multiplicative) role on the whole reactivity. Finally, the most active powder catalysts were wash-coated in a SiC monolith and tested in a bench-scale reactor. As a whole, the catalyzed monoliths performed the complete oxidation of either ethylene or propylene at lower temperatures (550 and 450 °C, respectively) than those required to thermally decompose these molecules. Graphic Abstract