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Nickel catalysts are vulnerable to suffering from carbon deposition and metal sintering in the methane dry reforming process under high temperature. Based on these problems, in this paper, La2O3–KIT-6 materials with different La2O3 contents were designed and prepared in order to take advantage of the basic sites of La2O3 and rich mesoporous structure of KIT-6, and then nickel catalysts supported on La2O3–KIT-6 materials were synthesized. In contrast, the Ni/KIT-6 catalyst was also prepared by the same method. XRD, TEM, SEM, physisorption of N2, XPS, H2-TPR, Raman, and TG were used for fresh and spent catalysts characterization in this work. The catalytic performance of these Ni/La2O3–KIT-6 catalysts was tested under high temperature methane dry reforming reaction. Our work showed that the La2O3-modified catalysts showed reasonably superior catalytic activity and high long term stability compared with the nickel catalyst supported on KIT-6 without modification of La2O3. The high dispersion of nickel nanoparticles on La2O3–KIT-6 as well as the basic property of La2O3 were both helpful to the resistance towards carbon deposition, and the interaction between Ni nanoparticles and support material in Ni/La2O3–KIT-6 was helpful to the resistance towards nickel sintering on account of the special physicochemical properties of La2O3. [ABSTRACT FROM AUTHOR]

Abstract: In this work, a new kind of heterostructured mesoporous materials (x%La2O3–MCF) for supporting nickel nanoparticles was developed by surface modification of mesoporous cellulous foam silica (MCF) with La2O3 in a monolayer/submonolayer state through an in situ growth method in order to make use of the advantages of mesoporous structure of MCF and basic sites of La2O3 at the same time. Nickel catalysts supported on these materials (Ni/x%La2O3–MCF) were prepared by impregnation method. The received mesoporous materials possessing predominant textural properties and thermal stabilities were investigated as catalysts for the carbon dioxide reforming of methane, exhibiting not only high activity but also good stability after a steady-state reaction for 10 h. The influence of La2O3 loadings on the performance of Ni/x%La2O3–MCF catalysts to the carbon dioxide reforming of methane was studied in this paper, and it was found that with La2O3 wt% = 10%, the Ni-based catalyst Ni/10%La2O3–MCF showed the highest activity, and exhibited superior stabilization. Several technologies were used to characterize the catalysts, such as transmission electron microscopy, X-ray diffraction patterns, physisorption of N2, X-ray photoelectron spectroscopy, carbon dioxide temperature programmed desorption and so on. The relationship between physicochemical properties of catalysts and catalytic performances has been investigated in detail.Graphical Abstract: A new kind of heterostructured mesoporous materials (x%La2O3–MCF) for supporting nickel nanoparticles was developed by surface modification of MCF with La2O3 in a monolayer/submonolayer state. The received mesoporous materials were investigated as catalysts for the carbon dioxide reforming of methane, exhibiting not only high activity but also good stability after a steady-state reaction for 10 h. [ABSTRACT FROM AUTHOR]