摘要
用瞬变应答／质谱在线检测技术研究了Ｎｉ／Ａｌ２Ｏ３催化剂上甲烷部分氧化制合成气的反应机理．研究结果指出，在常压９７３Ｋ条件下，Ｎｉ／Ａｌ２Ｏ３催化剂上甲烷部分氧化制合成气按直接氧化机理进行，Ｈ２和ＣＯ是甲烷部分氧化的一次产物，其主要反应可表示如下：１．ＣＨ４＋ｘＮｉ→ＮｉｘＣ＋２Ｈ２，２．Ｏ２＋２Ｎｉ→２ＮｉＯ，３．ＮｉｘＣ＋ＮｉＯ→ＣＯ＋（ｘ＋１）Ｎｉ．
Transient response technique equipped with on line quadruple mass spectrometer has been used to study the reaction mechanism of methane partial oxidation to syngas over an 8%(mol)Ni/Al 2O 3 catalyst at atmospheric pressure and 973 K. It is found that the metallic Ni sites play an important role in dissociation of methane and oxygen to form carbide (Ni x C) and NiO. CO is formed via carbide to react with surface NiO. H 2 and CO are the primary products of methane partial oxidation. In combination with pulse reaction experiments, it could be derived that methane partial oxidation to syngas accords with the direct oxidation mechanism, which can be described as follows:1. CH 4+ x NiNi x C+2H 2; 2. O 2+2Ni2NiO; 3. Ni x C+NiOCO+( x +1)Ni.
出处
《催化学报》
SCIE
CAS
CSCD
北大核心
1998年第4期309-314,共6页
基金
国家自然科学基金
关键词
甲烷
氧化
合成气
镍
氧化铝
催化剂
Methane, Partial oxidation, Syngas, Nickel, Alumina, Transient response, Reaction mechanism
