摘要
在反应条件，甲烷比催化剂上吸附的ＣＯ和Ｈ＿２都可分为可逆与不可逆吸附两类。甲烷的生成是可逆吸附氢与不可逆吸附ＣＯ作用的结果，可逆吸附ＣＯ只与生成乙烷等到产物有关。随着体系中氢分压的增加催化剂表面上可逆氢浓度增加，不可逆吸附ＣＯ则在较低一氧化碳分压下，吸附量先有所增加，后维持一恒定量。动力学研究结果表明，镍催化剂上甲烷化反应速率主要决定于表面不可逆ＣＯ浓度，因此镍催化剂上甲烷化反应无需加压进行。从而揭示了甲烷化反应的压力效应本质。
The frontal adsorption and reaction experiments are conducted With the pressure dynamicanalysis equipment.The results show that the adsorbed carbon monoxide and hydrogen on comme-rcial Ni catalyst can be distinguished as reversible and irreversible adsorption under real reactionconditions.The irreversibly adsorbed carbon monoxide and reversibly adsorbed hydrogen areresponsible for the formation of methane. The reversibly adsorbed carbon monoxide is relatedwith the formation of byproducts such as ethane,propane and others.The surface concentra-tion of irreversibly adsorbed hydrogen does not vary with pressure.The surface concentra-tion of reversible adsorption hydrogen increases with pressure.When pressure is lower thanatmospheric,the surface concentration of irreversibly adsorbed carbon monoxide increases withpressure,while concentration keeps constant.According to kinetic results, the methanationrate is mainlv decided by the surface concentration of carbon monoxide.However,when thepressure is higher than atmospheric,the surface concentration of irreversibly adsorbed carbonmonoxide does not increase with pressure.Therefore,methanation should be operated underatmospheric pressure.
出处
《石油化工》
CAS
CSCD
北大核心
1994年第4期216-220,共5页
Petrochemical Technology
基金
国家自然科学基金
关键词
甲烷化
压力效应
镍
催化剂
methanation,reversible adsorption,irreversible adsorption, pressure effect
