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Sulfur dioxide （SO2） is a serious pollutant in our country, so it is important toresearch flue gas desulfurization （FGD） and reuse SO2. In many FGD technologies,reducing sulfur dioxide directly in exhaust gases to sulfur over a catalyst is attractive,however, the presence of oxygen is a great problem. Therefore, researching anddeveloping novel catalyst for reduction of SO2 with CO in the presence of oxygen forFGD of coal-fired power plants is significant.In this paper, we use Y-doping to make the La1-XYXCoO3 （X = 0.1,0.3,0.5,0.7）catalysts . And then we studied the catalytic performance emphatically in the presenceof oxygen with sulfurized La1-XYXCoO3（X=0,0.1,0.3,0.5,0.7） catalysts, and mainlyinspected the activity and stability of sulfurized La0.7Y0.3CoO3 catalyst at eachcomponent with oxygen under the conditions of the SO2 reduction of CO. Using ofXPS, XRD and TPD, and other means of instruments, researched substitution ofyttrium in LaCoO3 under the conditions of the CO catalytic reduction properties ofSO2 with oxygen. Study found that, after sulfurized La1-XYXCoO3 （X=0.1,0.3,0.5,0.7）catalyst not only enhance the antioxidant properties but also made the temperaturemuch lower. The lifetime of the SO2 reduction of CO with sulfurized La0.7Y0.3CoO3 ascatalyst experiment results show that it can enhance and maintain the contentS2-species in sulfurized La0.7Y0.3CoO3 catalyst after substitution of yttrium in LaCoO3.The reaction temperature is lower than the previous results of 150℃.The influence of space velocity was obvious on the lower temperaturearea（300℃～350℃）,not on the higer temperature area（380℃～500℃）. The resultsshow that the ratio of CO/O2+SO2 is close to stoichiometric of combustion andreducing the desulfurization , the conversion rate of SO2 and element sulfur yield arealmost no influence, and it is the best materials ratio; O2 content on the conversion ofSO2 and the element sulfur yield have a little effection.By examining the structure of sulfurized La0.7Y0.3CoO3, found that the CoOcontent is closely related to the performance of CO reduction SO2; Y2S3 played a keyrole in reaction system to lower the temperature,when Y2S3 content is 15 wt.%, mixedcatalyst achieve to the longest life expectancy .
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