【摘要】 采用脉冲D2反应研究了CeO2在Co-CeO2/SiO2费托合成催化剂中的作用机理.通过比较在Co-CeO2/SiO2和Co/SiO2催化剂上的脉冲D2反应实验结果发现,CeO2可以提高载体表面Si-OH的H-D同位素交换活性和Si-OH中H参与CO加氢反应的活性;CeO2不仅增加了催化剂表面活性碳物种的总量,而且活性碳物种以链增长单体-CH2-为主,因而有利于增加费托合成反应速率和链增长几率;CeO2的加入明显提高了催化剂表面碳原子的加氢反应速率,从而减少了碳沉积.更多还原

【Abstract】 The role of the CeO₂ promoter in the Co-CeO₂/SiO₂ catalyst playing in Fischer-Tropsch synthesis （FTS） was investigated by means of the D₂ pulse reaction. The D₂ pulse reaction results over Co-CeO₂/SiO₂ and Co/SiO₂ catalysts showed that the addition of CeO₂ increased the catalytic activity of Co/SiO₂ for the H-D isotopic exchange and the reactivity of H from Si-OH for CO hydrogenation. The addition of CeO₂ increased the total amount of active carbon species on the surface of Co/SiO₂ and made the chain growth unit -CH₂- the dominating one, which consequently benefited the increase of the FTS reactivity and the chain growth possibility. The addition of CeO₂ into Co/SiO₂ also improved the hydrogenation reactivity of carbon atoms on the surface of Co-CeO₂/SiO₂, which led to a decrease in carbon deposition.更多还原