Bond-order conservation-Morse potential method has been some modified for alloy systems. Comparison with Ni(100) and Cu(100), syngas (CO+H~2) methanation activity on NiCu(100) has been studied. The results show, due to the introduction of Cu, methanation on NiCu has much lower activity than on Ni, which can be explained by the formation of deposited C~s from CO dissociation on Ni surfaces. Also, we investigate the rate-determining-step of methanation reaction on those surfaces, and the influences of the deposited surface species at reaction beginning on the reactivity of CO methanation.

Key words: HETERGENOUS CATALYSIS, NICKEL, NICKEL ALLOYS, COPPER, COPPER ALLOYS, CARBON DEPOSITS, METHANATION, SYNTHETIC GAS, SEDIMENTATION, SURFACE MODIFICATION