摘要
在费托反应合成烃类的研究方面,有关CO解离和碳化物形成机理已为众多的学者所接受。铁催化剂与合成气作用,易于生成碳化物和氧化物。一般认为碳化物是甲烷和链增长的中间物种。通过金属有机化合物的研究,M_4C、M_3CH,M_2CH_2和M_1CH_3(M=金属)均已被合成、分离和鉴定,并巳知这些碳化物的加氢活化能的顺序为M_4C>M_3CH>M_2CH_2>M_1CH_3。
Alumina-supported catalysts were prepared by impregnatinn A1_2O_3 with Fe(CO)_5, Fe_3(CO)_(12) or Fe_5C(CO)_(15) in n-hexane solution and [Me_4N]_2Fe_6C(CO)_(16)] in THF solution. The catalysts were tested for CO hydrogenation at 350℃, H_2/CO=1.2,0.5-2MPa and 500-1800h^(-1). The product distribution shows a sharp maximum at C_1-C_3 and a high selectivity to light olefins (C_2^(?)—C_3^(?)) .Catalysts prepared from carbidocarbonyl iron clusters exhibit higher activity than those from noncarbidocarbonyl iron compounds. In particular a very high conversion of CO was observed when [Me_4N]_2 [Fe_6C(CO)_(16)] was used as the catalyst precursor. Perhaps, Fe_nC is the active material for Fischer-Tropsch synthesis. Garbidocarbon acts as the growing point for chain propagation, facilitating chemical adsorption of CO and speeding up the reaction.
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
1992年第4期445-448,共4页
Journal of Fuel Chemistry and Technology
基金
国家自然科学基金委
中科院福建物构所
上海有机所开放实验室资助
关键词
碳络
羰基
碳烃
合成
carbidocarbonyl cluster
catalysis
FT reaction
