摘要
本文用过渡应答法研究了CO在含钾Fe-Co/Al_2O_3催化剂上的氢化反应,为含钾催化剂的吸附行为和反应机理提供了有益的信息。数据表明,H_2和CO在该催化剂上存在着部分不可逆吸附。二者吸附在同一个活性位上,CO的吸附略强于H_2的吸附。由产物应答实验可知催化剂上只存在一种活性中间体—表面碳。其碳链的增长不一定经过气相CO的插入。
The transient response method was used to study the dynamic behavior of CO hydrogenation over Fe-Co-K/γ-Al2O3 catalyst and a quadrupole mass spectrometer was used as a transient analytical tool. It is found that CO and H2 are adsorbed on the same surface sites. A part of CO or H2 is adsorbed irreversibly and the adsorption of CO is somewhat stronger than that of H2.The addition of K2O could suppress CO disproportionation and promote the formation of C-C bonds. According to the experimental results, it is suggested that the surface carbon produced by CO dissociation is the main active intermediate in the hydrocarbon formation, and the mechanism via gas CO insertion is unnecessary for the C-C formation.
