| 摘要 |
A mixed metal oxide catalyst (11) is described which permits the conversion of methane (18) to ethane, ethylene, and higher hydrocarbons at temperatures below 600 DEG C in the presence of oxygen (19) and steam (21) with selectivities of 80-100 % at methane conversions exceeding 10 %. The catalyst comprises an alkaline earth oxide, an oxide of a transition metal of groups VIB, VIIB and VIII of the periodic system and a small amount of an oxide of alkali. The catalyst is activated in oxygen and steam and remains active only in the presence of steam. This type of catalyst in the absence of steam and at temperatures above 600 DEG converts methane with oxygen to higher hydrocarbons and carbon dioxide with selectivities to hydrocarbons below 70 %. High selectivity approaching 100 % can be achieved with a preferred catalyst containing an atomic ratio of Ca:Ni:K of 2-4:1:0.05-0.5 after pretreatment of the catalyst in oxygen. |
