Catalytic combustion of benzene over γ-alumina supported chromium oxide catalysts

• Published in: Applied catalysis. A, General Vol. 468; pp. 269 - 275
• Main Authors: Xing, Tao, Wan, Haiqin, Shao, Yun, Han, Yuxiang, Xu, Zhaoyi, Zheng, Shourong
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 05.11.2013; Elsevier
• Subjects: Benzene; Catalysis; Catalysts; Catalytic combustion; Chemistry; Chromium; Chromium oxides; Combustion; Dispersions; Exact sciences and technology; General and physical chemistry; Monolayer dispersion; Surface chemistry; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; γ-Alumina supported chromia catalyst; Catalytic combustion; γ-Alumina supported chromia catalyst; Benzene; Monolayer dispersion; Heterogeneous catalysis; Binary compound; Chromium oxide; Transition element compounds; Alumina; Supported catalyst; Dispersion
• ISSN: 0926-860X; 1873-3875
• DOI: 10.1016/j.apcata.2013.08.054

•Chromia could be well dispersed on γ-Al2O3 with a monolayer dispersion capacity of 7.5wt.%.•For catalytic combustion of benzene the catalyst with a Cr loading near the monolayer dispersion capacity showed the best activity.•Surface Cr6+ played an important role for the benzene oxidation. The γ-alumina supported chromium oxide catalysts with Cr loadings varying from 1.7 to 13.6wt.% were prepared by the impregnation method and characterized using N2 adsorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV–vis spectroscopy and Raman spectroscopy. Benzene combustion catalyzed by the catalysts was investigated. The results showed that chromia was well dispersed on the surface of γ-Al2O3 with a monolayer dispersion capacity of 7.5wt.%. For the supported chromia catalyst with a Cr loading of 1.7wt.%, only Cr6+ species were observed. Increasing Cr loading to 5.1wt.% led to the presence of both Cr3+ and Cr6+ species. Catalytic benzene combustion over the catalysts was found to be strongly dependent on Cr loading amount. For supported chromia catalyst with a Cr loading of 8.5wt.%, complete benzene combustion was achieved at 350°C which was substantially lower than the temperature for other catalysts, indicating that supported chromia catalyst at a near monolayer dispersion capacity exhibited the optimum catalytic behavior for benzene combustion.