Bimetallic molybdenum-nickel catalysts supported on alumina have been studied in the carbon dioxide reforming of methane. Two different temperature-programmed reduction (TPR) pretreatments have been followed for their synthesis: using hydrogen to obtain metallic molybdenum and using a CH_4/H_2 reactant mixture to obtain molybdenum carbides, which have shown better performance in the reaction. Although in nickel catalysts the surface mobility of carbon species generated from methane decomposition leads to the accumulation of great amounts of carbon deposits in the support surface, the presence of molybdenum has been observed to avoid these migration processes. The synergic effect found between both metals in Ni-Mo bimetallic samples reduces the temperature of carburization of molybdenum, improves its catalytic activity and its selectivity to hydrogen in the CH_4+CO_2 reaction at the same time that avoids the formation of undesired carbon structures caused by methane decomposition.
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