F-T合成非负载型Fe-Mn催化剂的晶相结构与反应性能

Ｆｅ－Ｍｎ催化剂前驱体在焙烧时生成α（Ｆｅ１－ｙＭｎｙ）２Ｏ３、γ－（Ｍｎ，Ｆｅ）３Ｏ４和β-（Ｍｎ，Ｆｅ）２Ｏ３。焙烧过的前驱体在氢气氛中还原时生成（Ｆｅ１－ｘ、Ｍｎｘ）３Ｏ４、（Ｍｎ，Ｆｅ）３Ｏ４、Ｆｅ１－ｚＭｎｚＯ、（Ｍｎ，Ｆｅ）Ｏ和Ｆｅ０。当还原处理过的前驱体被置于合成气中时，随着反应环境的变化Ｆｅ０转变为碳化铁、Ｆｅ１－ｚＭｎ２Ｏ，最终成为（Ｆｅ１－ｘＭｎｘ）３Ｏ４。锰在催化剂中起着电子及结构双重作用。在催化过程中，所有的晶相均表现出一氧化碳加氢活性。然而，它们的催化性能与反应环境密切相关。

CRYSTAL PHASE AND PERFORMANCE IN LJNSUPPORTED Fe-Mn CATALYSTS FOR FISCHER-TROPSCH SYNTHESIS

|á-(Fe1-yMny)2O3, |?-(Mn, Fe)3O4 and |?-(Mn, Fe)2O3 are formed when Fe-Mn catalyst precursors are calcined. While (Fe1-xMnx)3O4, (Mn,Fe)3O4, Fe1-zMnzO, (Mn, Fe)O and Fe0 are formed when these calcined precursors are reduced in hydrogen. When exposed to syngas, these reduced precursors vary with the redox environment from Fe0 to iron carbides, Fe1-zMnzO, and finally to (Fe_1-xMn_x)_3O_4. Manganese plays both electronic and structural roles in the catalyst. All the crystal phases formed during synthesis exhibit catalytic activity to CO hydrogention.