Effect of Ce and Zr Addition to Ni/SiO2 Catalysts for Hydrogen Production through Ethanol Steam Reforming

Catalysts

Jose Antonio Calles¹  Alicia Carrero²  Arturo Javier Vizcaíno²  Monta༚ Lindo²  Morris D. Argyle² 

[1] Department of Chemical and Energy Technology, Rey Juan Carlos Universtity, c/Tulipán, s/n, Móstoles 28933, Spain;

关键词: nickel catalyst;    ceria;    zirconia;    promoter;    coke;    impregnation order;   

DOI  :  10.3390/catal5010058

来源: mdpi

【 摘 要 】

A series of Ni/Ce_xZr_1−xO₂/SiO₂ catalysts with different Zr/Ce mass ratios were prepared by incipient wetness impregnation. Ni/SiO₂, Ni/CeO₂ and Ni/ZrO₂ were also prepared as reference materials to compare. Catalysts’ performances were tested in ethanol steam reforming for hydrogen production and characterized by XRD, H₂-temperature programmed reduction (TPR), NH₃-temperature programmed desorption (TPD), TEM, ICP-AES and N₂-sorption measurements. The Ni/SiO₂ catalyst led to a higher hydrogen selectivity than Ni/CeO₂ and Ni/ZrO₂, but it could not maintain complete ethanol conversion due to deactivation. The incorporation of Ce or Zr prior to Ni on the silica support resulted in catalysts with better performance for steam reforming, keeping complete ethanol conversion over time. When both Zr and Ce were incorporated into the catalyst, Ce_xZr_1−xO₂ solid solution was formed, as confirmed by XRD analyses. TPR results revealed stronger Ni-support interaction in the Ce_xZr_1−xO₂-modified catalysts than in Ni/SiO₂ one, which can be attributed to an increase of the dispersion of Ni species. All of the Ni/Ce_xZr_1−xO₂/SiO₂ catalysts exhibited good catalytic activity and stability after 8 h of time on stream at 600 °C . The best catalytic performance in terms of hydrogen selectivity was achieved when the Zr/Ce mass ratio was three.

【 授权许可】

CC BY   
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