RhCo双金属催化剂的研究 Ⅲ.Rh+Co/A1_2O_3上表面羰基氢化物及其动态行为  

Study of RhCo Bimetallic Catalysts III . Surface Carbonyl Hydride and Their Dynamic Behavior on Rh+ Co/Al_2O_3

作　　者：陈耀强[1] 龚茂初[1] 曹昭[1] 周建略 陈豫[1] 辛勤[2] 张慧[2] 郭燮贤[2] 

机构地区：[1]四川大学化学系,成都610064 [2]中国科学院大连化学物理研究所,大连116023

出　　处：《化学学报》1997年第7期632-637,共6页Acta Chimica Sinica

基　　金：国家自然科学基金;催化基础研究国家重点实验室基金资助课题

摘　　要：利用连续流动微反研究了Rh+Co/Al_2O_3催化剂的CO加氢反应.结果表明反应在220℃以上发生.反应活性随温度的升高和H_2/CO值的增加而增加.利用TP-IR动态方法研究了Rh+Co/Al_2_3上CO和H_2共吸附及其动态行为.结果表明在Rh+Co/Al_2O_3的孪生及线式中心上,CO和H_2室温共吸附时即有部分孪生及线式CO转化为相应的羰基氢化物.随温度的升高,剩余的孪生和线式CO继续向相应的羰基氢化物转化.而羰基氢化物则向多氢羰基氢化物转化.在到达反应温度之前,催化剂表面只存在羰基氢化物及相应的多氢羰基氢化物.在反应温度则导致产物CH_4生成.与CO加氢反应和CO歧化的吸附态研究结果相关联,作者认为在Rh+Co/Al_2O3上CO加氢生成CH_4是经由羰基氢化物-多氢羰基氢化物途径.CD hydrogenation of Rh + Co/Al2O3 has been studied by using a flow micro - reactor.CO hydrogenation took place over 220℃ and reaction activity increased with the reaction temperature and H2/CO ratio. Coadsorption of CO and H2 as well as dynamic behavior of coadsorbed CO and H2 have been investigated by TP - IR dynamic method. The results indicatethat in coadsorption of CO and H2 at 20℃ ,gem - dicarbonyl CO and linear CO transformed partly into the corresponding carbonyl hydride. With increasing the temperature, the residual gem -dicarbonyl CO and linear CO transformed also into the corresponding carbonyl hydride, while the carbonyl hydrides transformed into the multi - hydrogen carbonyl hydrides. Before arriving at the reaction temperature, there are only the carbonyl hydrides and the multi - hydrogen carbonyl hydride which led to the formation of CH4 at the reaction temperature on the surface of Rh + Co/Al2O3. To relate these results with the results obtained in CO hydrogenation and in CO disproportionation. We believe that in CO hydrogenation reaction, the scission of C-O bond is via the carbonyl hydride - multihydrogen carbonyl hydride.

关 键 词：铑 钴 双金属催化剂 催化剂 一氧化碳 加氢 

分 类 号：O643.36[理学—物理化学] O613.71[理学—化学]