Lanthanide oxide modified nickel supported on mesoporous silica catalysts for dry reforming of methane

Addition of rare earth oxide, especially lanthanide oxide, was regarded as a promising strategy to improve the carbon resistance for Nickel-based catalysts in dry reforming of methane (DRM). In this work, Nickel-based catalysts containing lanthanide oxides (NiLa/SiO 2 , NiCe/SiO 2 , NiSm/SiO 2 , and NiGd/SiO 2 ) were prepared and employed to catalyze DRM. Lanthanide oxide affected the formation of Ni nanoparticles in different size. In NiLa/SiO 2 and NiCe/SiO 2 , Ni nanoparticles maintained relatively small size (4 nm), while in NiSm/SiO 2 and NiGd/SiO 2 , nickel particles were in large size (8 nm). NiLa/SiO 2 and NiCe/SiO 2 exhibited better stability than the other two catalysts, with CH 4 conversion decreasing from 64.6 to 57.6% and 61.6 to 60.3%, respectively in 10 h on stream. The kinetic study confirmed that adding lanthanide oxide significantly affected the activation energy of CH 4 dissociation and CO 2 dissociation. Compared to monometallic Ni/SiO 2 , the presence of Sm and Gd suppressed CO 2 dissociation, and introduction of Ce and La effectively promoted CO 2 dissociation. These characters contributed to the higher carbon resistance and good stability for NiLa/SiO 2 and NiCe/SiO 2 catalysts in DRM reaction.