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用高温熔融法制备了不同化学组成的氨合成铁基催化剂．利用催化反应评价、物理吸附技术、ＸＲＤ和Ｍｏｓｓｂａｕｅｒ谱技术研究了助催化剂对Ｆｅ１－ｘＯ基和Ｆｅ３Ｏ４基催化剂的活性、比表面积和孔结构的影响．结果表明，在助催化剂不存在的情况下，活化态Ｆｅ１－ｘＯ基催化剂的比活性明显高于活化态Ｆｅ３Ｏ４基催化剂．助催化剂对熔铁催化剂的促进作用与其母体相组成密切相关，ＣａＯ和Ａｌ２Ｏ３分别是Ｆｅ１－ｘＯ基和Ｆｅ３Ｏ４基催化剂的重要结构助剂．在多种助催化剂存在的情况下，结构助剂在一定程度上影响着电子助剂的效能．
Ammonia synthetic iron-based catalysts with different chemical compositions were prepared by high temperature melting method. The effects of promoters on the activity, specific surface area and pore structure of Fe1-xO and Fe3O4-based catalysts were investigated by catalytic reaction evaluation, physical adsorption, XRD and Mossbauer spectroscopy. The results showed that the specific activity of the activated Fe1-xO-based catalyst was significantly higher than that of the activated Fe3O4-based catalyst in the absence of co-catalyst. The promoting effect of cocatalyst on the melting iron catalyst is closely related to its parent phase composition. CaO and Al2O3 are important structural aids for Fe1-xO-based and Fe3O4-based catalysts, respectively. In the presence of a variety of cocatalysts, structural aids affect the effectiveness of electronic aids to a certain extent.