Catalytic oxidation of CO and toluene over nanostructured mesoporous NiO/Ce0.8Zr0.2O2 catalysts

Abstract

Mesoporous Ce 0.8 Zr 0.2 O 2 oxides were prepared by a surfactant-assisted method of nanocrystalline particle assembly, and used as a support of nickel oxide nanocatalysts. The obtained mesoporous NiO/Ce 0.8 Zr 0.2 O 2 nanocatalysts were characterized by XRD, N 2 adsorption, TEM, H 2 -TPR and X-ray photoelectron spectroscopy techniques. The catalytic properties of the NiO/Ce 0.8 Zr 0.2 O 2 nanocatalysts were evaluated by CO oxidation and toluene combustion. The results showed that the catalyst with 10 wt% NiO loading exhibited the highest catalytic activity for CO oxidation and toluene combustion.

In situ valence modification of Pd/NiO nano-catalysts in supercritical water towards toluene oxidation

“…2d displayed three O1s BE peaks at approximately 529.3, 531.0 and 532.5 eV, associating with the surface lattice oxygen, chemisorbed oxygen and hydroxyl (and/or carbonate) species, respectively. 30 The ratio of chemisorbed oxygen to lattice oxygen (Oad/Olat) also showed a trend of sc-Pd/NiO > sc-Pd/NiO-R > sc-NiO, which was in line with that of Ni 3+ :Ni 2+ . Fig.…”

Selective oxidation of cyclohexane: Ce promotion of nanostructured manganese tungstate

“…4a. The Ce 3d XPS is complex and composed of two multiplets (v and u) corresponding to the Ce 3d 5/2 and Ce 3d 3/2 core holes and in cerium oxide materials both multiplets have contributions from the Ce 3+ and Ce 4+ oxidation states [24,38,[42][43][44][45]. The Ce 3d XPS of 1%Ce-MnWO 4 (Fig.…”

“…MnCeO x solid solutions have shown remarkable results for cyclohexane selective oxidation to KA oil in the liquid at mild conditions [21], and in continuous gas phase reaction at 180°C [22]. Indeed, CeO 2 has been applied extensively in the formulation of catalysts for various oxidation reactions including of carbon monoxide [23,24], alcohols [25,26] and hydrocarbons [21,22,[27][28][29][30], due to the effectiveness of the Ce 3+ /Ce 4+ redox pair in creating oxygen vacancies thereby increasing the oxygen ion mobility and oxygen storage capacity, which can be enhanced by doping transition metals into the ceria cubic fluorite lattice. Based on this literature it seems probable, therefore, that nanostructured MnWO 4 [20] might be a promising catalyst for cyclohexane selective oxidation although this has not been investigated to date.…”

Preparation of NiO/CeO₂ Catalysts by Solid State Impregnation and Their Application in CO Oxidation

“…5 有研究报道表明, 镍铈 催化剂作为重要的铈基催化剂, 在 CO 氧化、 CH4重 整等反应中表现出良好活性. 6,7 对于 NiO-CeO2体系, 理论计算和实验结果都表明通过在二氧化铈晶格 中掺入 Ni 2 + , 会形成氧空位, 继而产生表面吸附氧, 加强氧物种的缓冲能力. 8,9 为了增强镍铈之间的相互 作用, 制备催化剂时镍盐和铈盐前驱体应紧密接触 以避免出现相分离.…”