甲烷催化部分氧化制合成气的反应机理

借助脉冲反应、质谱-程序升温表面反应（MS-TPSR）等技术研究了Ni／α-Al2O3催化剂上甲烷催化部分氧化制合成气（POM）的反应机理．结果表明，NiO上CH4不能解离产生H2只有当NiO被CH4还原为Ni0后，CH4才能解高产生H2，Ni0是CH4活化和POM反应的活性相；POM反应机理遵循直接氧化机理，CH4和O2均在Ni0上活化，活化过程形成的Ni…C和Niδ…Oδ物种是反应历程中的关键物种，Niδ …Oδ物种高选择性地与CH4解离产生的碳物种Ni…C反应生成CO．

Mechanism of Catalytic Partial Oxidation of Methane to Synthesis Gas on Nickel Catalyst

Pulse reaction and MS-TPSR (temperature programmed surface reaction, equipped with on line mass spectroscopy) techniques were employed to study the methanism of catalytic partial oxidation of methane to syngas over nickel catalysts. The deep oxidation of methane by lattice oxygen species to CO2 and H2O took place on NiO/Al2O3 catalysts, While on metallic nickel catalysts Ni0/Al2O3 methane activation followed the pyrolysis mechanism to produce H2 and surface carbon species Ni...C. The mechanism for methane partial oxidation should follow the direct oxidation route. Both methane and oxygen are activated on metallic nickel sites to form active surface species of Ni…C and Niδ+… Oδ-. H2 and CO are the primary products directly formed by the reaction of Ni…C with Niδ+…Oδ-.