Precursor influence and catalytic behaviour of Ni/CeO2 and Ni/SiC catalysts for the tri-reforming process Original Research Article

The aim of the work described here is to evaluate the catalytic performance in the tri-reforming process of Ni/CeO2 and Ni/β-SiC catalysts prepared by using four different nickel salts (nitrate, acetate, chloride and citrate). Metal particles supported over ceria had bigger particle sizes (leading to lower metal-support interactions) than those supported on β-SiC. It was also demonstrated that the metal salt used in the preparation of Ni-based catalysts had a marked influence on the size of the nickel particles. Larger particles with a worse catalytic behaviour were obtained when nickel chloride and nickel citrate were used as the precursors of Ni supported species. Methane consumption rate and H2/CO ratio in the effluents were influenced by the type of support and salt precursor used in the preparation of the catalysts. CO2-TPD proved that catalysts based on ceria as the support presented more basic sites, which was related to a decrease of the H2/CO molar ratio in the effluents coming from the reactor. High methane consumption rate and good catalytic stability were obtained when nickel nitrate and nickel acetate were used to prepare Ni/β-SiC catalysts. The results showed that these latter catalysts can be considered as promising ones for the tri-reforming process.