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采用浸渍法制备了负载型CeO2 /γ Al2 O3 ,La2 O3 /γ Al2 O3 和CeO2 La2 O3 /γ Al2 O3 催化剂 ,并用XRD和XPS对催化剂进行了表征 ,在n(SO2 ) /n(CO) =1/ 3,载流气体为N2 ,气体流量为 1L/min ,催化剂用量为 15 g的条件下 ,考察了催化剂催化CO还原SO2 反应的性能 ,研究了催化剂的活化过程、催化活性和反应物配比对活性的影响 .结果表明 ,CeO2 La2 O3 /γ Al2 O3 在催化还原SO2 反应中的活化温度比单组分催化剂CeO2 /γ Al2 O3 或La2 O3 /γ Al2 O3 下降了 5 0～ 10 0℃ ,而且具有更高的活性 .这可以解释为由CeO2 的redox反应与La2 O3 的COS中间物反应之间的协同作用所致 .还对SO2 还原反应机理进行了探讨 ,发现CeO2 的redox反应所生成的单质硫是整个过程中COS中间物反应的重要来源 .在此基础上 ,对CeO2 La2 O3 /γ Al2 O3 催化CO还原SO2 反应提出了redox COS叠加反应机理 .
The supported catalysts CeO2 / γ Al2 O3, La2 O3 / γ Al2 O3 and CeO2 La2 O3 / γ Al2 O3 were prepared by impregnation method. The catalysts were characterized by XRD and XPS. 1/3, the carrier gas is N2, the gas flow rate is 1L / min, the amount of catalyst is 15 g, the catalytic performance of the catalyst for the reduction of SO2 by CO is investigated. The activation process, catalytic activity and reactant The results showed that the activation temperature of CeO2 La2 O3 / γ Al2 O3 in the catalytic reduction of SO2 was 50 ~ 100 ℃ lower than that of single-component catalysts CeO2 / γ Al2 O3 or La2 O3 / γ Al2 O3 , Which is explained by the synergism between the redox reaction of CeO2 and the COS intermediate of La 2 O 3.The mechanism of SO 2 reduction reaction was also discussed and it was found that the redox reaction of CeO 2 generated Elemental sulfur is an important source of COS intermediate reaction in the whole process.On the basis of this, a redox COS superposition reaction mechanism is proposed for the reduction of SO2 by CO 2 catalyzed by CO 2 La 2 O 3 / γ Al 2 O 3.