Synergy effects of CeO 2 and CaO on the conversion of cyano-containing exhaust gases with Ni-based catalyst

Ni/CeO 2 /CaO-MgO catalyst was prepared to catalyze the conversion of cyano-containing exhaust gases into clean fuel gases. Almost all of the large molecular weight cyano-containing compounds were converted into fuel gases with 91.5% reduction of HCN being observed at 650 °C. The introduction of water-steam into the reaction system could further increase the conversion of HCN as well as the production of H 2 . During the 16 h stability test, the conversion of model compound benzonitrile could be kept around 100% with little carbon deposited. The prepared catalysts were characterized by XRD, H 2 -TPR, XPS, SEM–EDS and TGA. The effect of CaO and CeO 2 modification was investigated. CaO improves the catalyst reducibility and basic properties which are beneficial to the reactants adsorption. CeO 2 addition strengthens the oxygen mobility and improves nickel dispersion over the catalyst. The excellent catalytic efficiency and stability could be attributed to the synergy effects of CaO and CeO 2 in the catalyst.