TPSR法研究F-T合成铁基催化剂碳物种的形成和反应性

STUDIES OF THE FORM AND REACTIVITY OF CARBONACEOUS SPECIES DEPOSITED ON IRON CATALYSTS FOR F-T SYNTHESIS BY TPSR

本文采用程序升温表面反应(TPSR)方法,研究了熔铁和沉淀铁催化剂于不同条件下CO、CO/H_2吸附后,在催化剂表面形成的不同加氢活性碳物种的形态和反应性。结果表明,温度对CO解离起重要作用,氢促进了CO的解离和碳化,碳化后催化剂上的CO/H_2吸附,使催化剂表面产生丰富的加氢活性高的α′碳物种。助剂K_2O具有电子效应,可调节催化剂上碳物种的加氢性能。长时间或高温陈化使表面碳活性下降。

Reactivity of carbonaceous species formed on the surfaces of fused iron and precipitated iron catalysls by adsorption of carbon monoxide and synthesis gas under different conditiones have been studied by temperature programmed surface reaction of the species with hydrogen. It has been found that hydrogen promotes the dissociation of carbon monoxide and carburization of iron. By the adsorption of CO/H_2 on a carbided catalyst, a very reactive carbon species α' is formed. The promotes K_2O、SiO_2、Al_2O_3 and MgO regulates the reactivity of the carbonaceous species formed on catalyst toward hydrogenation.