SO_2对La_(0.8)K_(0.2)Cu_(0.05)Mn_(0.95)O_3钙钛矿催化剂氧化碳烟的影响  

Effect of SO_2 on Soot Oxidation over La_(0.8)K_(0.2)Cu_(0.05)Mn_(0.95)O_3 Perovskites-type Catalyst

作　　者：乐向晖[1] 张栖[1] 付名利[1] 黄碧纯[1] 梁红[2] 叶代启[1] 

机构地区：[1]华南理工大学环境科学与工程学院,广州510006 [2]广州大学化学化工学院,广州510006

出　　处：《无机化学学报》2009年第7期1170-1176,共7页Chinese Journal of Inorganic Chemistry

基　　金：广东高校科技成果转化项目[No.粤教科(2009)13号(cgzhzd0803)];广东省自然科学基金(No.8151009101000025);广东省社会发展科技(No.2007B030102006);广州市属高校科技项目(No.62008)资助

摘　　要：采用柠檬酸配位法制备K、Cu掺杂的La0.8K0.2Cu0.05Mn0.95O3钙钛矿催化剂,运用程序升温氧化(TPO)考察在不同浓度SO2气氛下La0.8K0.2Cu0.05Mn0.95O3催化剂催化氧化模拟碳黑的性能,并用XRD、FTIR和XPS等进行表征。结果表明,催化剂在0～0.1%的SO2气氛中呈现出不同活性,φSO2≤0.05%的气氛可促进催化剂催化氧化碳黑的活性,当φSO2=0.03%时,催化剂活性最高;引入φSO2≥0.06%时催化剂活性明显下降。XPS说明表面活性氧的增加是低浓度的SO2促进催化活性的原因,同时XRD、FTIR结果表明高浓度的SO2所产生的大量SO42-是抑制催化剂活性的原因。La0.8K0.2Cu0.05Mn0.95O3 catalysts were prepared using the citrate acid-complex combustion method. Catalysts were characterized with XRD, FTIR, XPS. Temperature programmed oxidation（TPO） tests were performed to evaluate the catalytic activity for soot oxidation in a feed gas containing various concentrations of SO2. The TPO results revealed that the catalysts exhibited different activities with 0-0.1% SO2 in feed gas. The performance of the catalyst was enhanced with SO2 concentration below 0.05%, and 0.03% SO2 resulted in the highest activity. However, the soot oxidation rate decreased when the SO2 feed concentration was above 0.06%. The results of XPS indicated that the increase of weakly chemisorbed O^- surface species was responsible for the excellent performance of La0.8K0.2Cu0.05Mn0.95O3 with lower concentration of SO2. The XRD and FTIR results revealed that plentiful SO4^2- was produced on the catalyst surface when SO2 coneentration was high, which could account for the loss of activity of the La0.8K0.2Cu0.05Mn0.95O3 catalyst.

关 键 词：二氧化硫 钙钛矿催化剂 碳烟氧化 表面活性氧 

分 类 号：O614.331[理学—无机化学] O614.113[理学—化学]