摘要
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.
Pulse reaction and MS-TPSR (tempeature progranund surface reaction, equipped with on line mass spectroscopy) techniques were employed to study the methwhsm of catalgtic partial oxidation of methane to syngas over nicke catalysts. The deep oxidation of methane by lattice oxygen species to CO2 and H2O took place on NiO/Al2O3 cataiysts, While on metallic nickel catalysts Ni0/Al2O3 methane activation followed the pyrolysis mechedsm to produce H2 and surface carbon species Ni...C. The mechanism for methane partial oxidation should folow the diret oxidation route. Both methane and oxygen are achvated on metallic nickel sites to form active surface species of Ni…C and Niδ+… Oδ. H2 and CO are the primmp products directly formed by the reachon of Ni…C with Niδ+…Oδ.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
1999年第4期313-318,共6页
Acta Physico-Chimica Sinica
关键词
甲烷
部分氧化
合成气
镍
催化剂
POM
Methane, Catalytic partial oxidation, Synthesis gas, Mechanism, Nickel catalyst