合成气(CO+H_2)在Ni,Cu及Ni-Cu合金上甲烷化反应的键级守恒法能学研究  

An Energetics Study on Syngas (CO + H_2) Methanation Reaction on Ni, Cu and Ni - Cu Alloy Surfaces by Bond - order Conservation Model

作　　者：夏文生[1] 汪海有[1] 万惠霖[1] 张乾二[1] 

机构地区：[1]厦门大学化学系物理化学研究所 固体表面物理化学国家重点实验室,厦门361005

出　　处：《化学学报》1998年第8期773-779,共7页Acta Chimica Sinica

基　　金：国家自然科学基金(29392006及29290300-03);国家重点实验室资助项目

摘　　要：将键级守恒-Morse势方法应用于合金体系,作了部分修正.通过与Ni(100),Cu(100)比较,研究了NiCu(100)上合成气甲烷化反应活性.表明,因Cu的加入,NiCu上甲烷化反应活性较Ni上显著降低,并通过CO在Ni上解离形成的积碳现象给予了解释.此外,还考察了甲烷化反应的速控步骤,及因解离物种可能在表面上的沉积使表面有所改性,从而影响CO甲烷化表面反应的活性.Bond - order conservation - Morse potential method has been some modified for alloy systems. Comparison with Ni(100) and Cu(100), syngas (CO + H2) 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 Csfrom 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.

关 键 词：键级守恒 甲烷化反应 催化剂 合成气 镍铜合金 

分 类 号：O643.36[理学—物理化学] O623.11[理学—化学]