摘要
研究了四种载体MgO ,α Al2 O3 ,γ Al2 O3 ,Ce γ Al2 O3 负载Fe催化剂上CO还原SO2 的反应。结果发现 ,以不同载体制备的催化剂上反应的活性和选择性具有相同的顺序 ,即Ce γ Al2 O3 >γ Al2 O3 >α Al2 O3 >MgO。BET表面积测试表明 ,比表面较大的载体有利于提高催化剂的活性 ,而XRD结果证明 ,催化剂的活性大小关键取决于反应过程中是否形成了催化活性相FeS2 ,只有生成FeS2 的催化剂才会在反应过程中表现出活性 ,TPR和TG实验证实 ,催化剂表面氧化还原能力越强越有利于形成FeS2 ,从而在反应过程中表现的活性也越高 ,Ce对γ Al2 O3 的改性一方面促进了反应过程中活性相FeS2 的形成 ,另一方面为反应提供了所需的氧空位 ,使整个反应表现出中间产物机理和氧空位机理的协同效应。
The reduction of sulfur dioxide by carbon monoxide over the iron oxide supported by several types of su pports (MgO,α Al 2O 3,γ Al 2O 3,Ce γ Al 2O 3 ) was studied The results demonstrated that the SO 2 conversion efficiency and the sulfur selectivity exhibit the following order: Ce γ Al 2O 3>γ Al 2O 3 >α Al 2O 3 >MgO The results of BET showed that the surface area plays an important role in catalyst activity XRD result revealed that the transformation of Fe 2O 3 to the FeS 2 during the reaction, it it could be concluded that FeS 2 was catalytically active The results of TPR and TG indicated that the sulfidization of catalyst is closely related to the surface reaction behavior of catalyst It was found that using Ce modifying γ Al 2O 3 can improve the formation of FeS 2 and offer the oxygen vacancy in reaction The redox mechanism was confirmed to be the simultaneous contribution from both COS intermediate mechanism and oxygen vacancy mechanism
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2002年第2期156-161,共6页
Journal of Fuel Chemistry and Technology
基金
天津市青年自然科学基金 (983 60 4711)~~
关键词
载体
Fe催化剂
二氧化硫
催化还原
support
iron catalyst
sulfur dioxide
catalytic reduction
