Improving Catalytic Stability and Coke Resistance of Ni/Al2O3 Catalysts with Ce Promoter for Relatively Low Temperature Dry Reforming of Methane Reaction

• Published in: Chemical research in Chinese universities 2022-08, Vol.38 (4), p.1032-1040
• Main Authors: He, Lulu, Chen, Xin, Ren, Yuanhang, Yue, Bin, Tsang, Shik Chi Edman, He, Heyong
• Format: Article
• Language: English
• Subjects: Aluminum oxide; Analytical Chemistry; Carbon; Catalysts; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Coke; Deposition; Desorption; Diffusion; Emission analysis; Fourier transforms; Inductively coupled plasma; Industrial applications; Infrared analysis; Infrared spectra; Inorganic Chemistry; Low temperature; Methane; Nanoparticles; Organic Chemistry; Photoelectrons; Physical Chemistry; Reforming; Sintering; Spectrum analysis; Stability tests; X ray photoelectron spectroscopy
• ISSN: 1005-9040; 2210-3171
• DOI: 10.1007/s40242-021-1281-5

A series of Ni catalysts supported on alumina with different Ce contents(1.0%–6.0%, mass fraction) was prepared by the impregnation method and used for dry reforming of methane(DRM) at a relatively low temperature of 650 °C. The promotion effect of Ce with different loading amounts on the physicochemical properties of the catalysts was systematically characterized by transmission electron microscopy(TEM), X-ray diffraction(XRD), N 2 adsorption-desorption, thermo elemental IRIS Intrepid inductively coupled plasma atomic emission spectrometer (ICP-AES), UV-visible diffuse reflectance spectroscopy(UV-Vis DRS), Fourier transformation infrared(FTIR) spectra, H2-temperature programmed reduction(H 2 -TPR) analysis, H2-temperature programmed desorption(H 2 -TPD), and The X-ray photoelectron spectroscopy(XPS) techniques. The results indicate that all the catalysts mainly exist in the NiAl 2 O 4 phase after being calcined at 750 °C with small Ni particle sizes due to the strong metal-support interaction derived from the reduction of the NiAl 2 O 4 phase. The Ce-promoted catalysts show better catalytic performance as well as the resistance against sintering of Ni particles and deposition of carbon compared to the Ni/Al 2 O 3 catalyst. The Ni-6Ce/Al 2 O 3 exhibits the best catalytic stability and coke resistance among the four catalysts studied, which is due to its small Ni nanoparticles sizes, excellent reducibility as well as high amount of active oxygen species. In a 400 h stability test for DRM reaction at 650 °C, Ni-6Ce/Al 2 O 3 exhibits less coke deposition and small growth of Ni nanoparticles. This work provides a simple way to preparing the Ni-Ce/Al 2 O 3 catalyst with enhanced catalytic performance in DRM. The Ni-6Ce/Al 2 O 3 catalyst has great potential for industrial application due to its anti-sintering ability and resistance to carbon deposition.