Catalytic oxidation of volatile organic compounds (n-hexane, benzene, toluene, o-xylene) promoted by cobalt catalysts supported on γ-Al2O3-CeO2

Abstract

-Cobalt catalysts supported on γ-alumina, ceria and γ-alumina-ceria, with 10 or 20%wt of cobalt load, prepared by the wet impregnation method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), field emission transmission electron microscopy (FETEM), N 2 adsorptiondesorption isotherms (BET/BJH methods), energy-dispersive X-ray spectroscopy (EDX), X-ray photoemission spectroscopy (XPS), O 2 -chemisorption and temperature programmed reduction (TPR) were used to promote the oxidation of volatile organic compounds (n-hexane, benzene, toluene and o-xylene). For a range of low temperatures (50-350 °C), the activity of the catalysts with a higher cobalt load (20% wt) was greater than that of the catalysts with a lower cobalt load (10% wt). The Co/γ-Al 2 O 3 -CeO 2 catalytic systems presented the best performances. The results obtained in the characterization suggest that the higher catalytic activity of the Co 20 /γ-Al 2 O 3 -CeO 2 catalyst may be attributed to the higher metal content and amount of oxygen vacancies, as well as the effects of the interaction between the cobalt and the alumina and cerium oxides.

A Co3O4–CeO2 functionalized SBA-15 monolith with a three-dimensional framework improves NOx-assisted soot combustion

“…As reported, the proper loading of Co 3 O 4 -CeO 2 (e.g. 2-Co 0.2 Ce 0.8 /SM) on SM can enhance the dispersion of Co 3 O 4 -CeO 2 and weaken the interaction between the metal oxides and the SM, thus improving the redox ability 28 and surface oxygen mobility, 31 which is helpful to the soot oxidation.…”

OXIDATION OF PHENOL IN AQUEOUS SOLUTION WITH COPPER OXIDE CATALYSTS SUPPORTED ON γ-Al2O3, PILLARED CLAY AND TiO2: COMPARISON OF THE PERFORMANCE AND COSTS ASSOCIATED WITH EACH CATALYST

“…Among the materials studied, γ-Al 2 O 3 is one of the best (Massa et al, 2009). Other support materials, such as silica (Njiribeako et al, 1978), activated carbon (Brainer et al,2014), pillared clay (Carriazo et al, 2005), TiO 2 (Dükkancý and Gündüz, 2009), MCM-41 (Eimer, 2006), ZSM-5 (Valkaj et al, 2007), Ce and Ce-Zr oxides (Nousir et al, 2008), γ-Al 2 O 3 -CeO 2 (Balzer et al, 2014) and polymeric membranes (Molinari at al., 2009), are promising materials and are being increasingly used as catalytic oxidation supports.…”

Gallium-Containing Mesoporous Silica: Supported Catalysts with High Catalytic Activity for Oxidation of Benzene, Toluene ando-Xylene

“…It has been previously noted that when aromatic compounds are associated with methyl groups they are not easily oxidized as benzene. 10,11 Blank of the reaction using mesoporous silica MCM-41 (without gallium) did not showed catalytic activity.…”

“…[7][8][9] All three substances are known to be toxic. 10,11 Several VOC removal technologies, such as flame combustion, catalytic combustion, catalytic destruction using ozone and plasma, photocatalytic decomposition, adsorption processes and biological treatment, have been developed to eliminate VOCs. 2,6,[12][13][14] Catalytic oxidation is considered to be the most effective approach, mainly due to its high efficiency in the degradation to carbon dioxide and water, even in effluents with low concentrations of VOCs, and low energy cost.…”