عنوان مقاله [English]
Mesoporous nanocrystalline zirconia powders with high specific surface area and stable tetragonal crystallite phase were prepared by surfactant assisted precipitation method. The obtained results showed that the nanocrystalline zirconia powders have a good potentional as catalyst support in natural gas reforming with carbon dioxide. The activity results indicated that the nickel catalyst with 5 wt.% nickel loading showed stable activity for syngas production with a decrease of about 4% in methane conversion after 50 h of reaction. Addition of promoters (CeO2, La2O3, MgO and K2O) to the catalyst improved both the activity and stability of the nickel catalyst and increased the nickel dispersion and had a positive effect in preventing coke formation. The nickel catalyst (5% Ni–3% CeO2/ZrO2) showed high catalytic stability under severe reaction conditions for more than 1550 h on stream. Based on our knowledge, there is no prior documentation for a nickel catalyst that is comparable to this catalyst in catalyst stability under the reaction conditions employed in this study.
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