摘要
利用La0.8K0.2Mn0.95Cu0.05O3氧化模拟碳烟,考察预硫化处理及程序升温氧化中SO2对催化剂性能的影响。采用H2-TPR,FTIR和XPS等方法对催化剂性能进行了表征。XPS表明催化剂在0.02%SO2气氛中400℃下进行4 h的预硫化后OI(O2-)转化为OII(O-),催化剂活性增加;TPO反应中低浓度SO2(0.01%)促进了催化剂的活性,可能是较高温度下高活性K的存在,有效阻止了硫酸盐的生成及积累,对O-的消耗减少。催化剂在0.02%SO2气氛中300℃下预硫化超过1 h以后活性明显降低,预硫化1.5 h后催化剂表面的O2-几乎消耗完全,O-大大减少,二者都转化为O(O2-);可能是较低温度下硫酸盐逐渐积累,加快了O2-的消耗,导致可用的氧源枯竭,催化剂活性降低。
The La0.8K0.2Cu0.05Mn0.95O3 was used to oxidize model soot,and the effect of SO2 in presulfation treatment or TPO test atmosphere on catalyst performance was investigated.The catalysts were characterized with H2-TPR,FTIR and XPS.The XPS revealed that the ample OII（O-） was produced from OI（O2-） after presulfated with 0.02% SO2 at 400 ℃ for 4 h,thus promoting catalyst activity.Also 0.01%SO2 in TPO improved catalyst activity.It was probably due to that K,with excellent activity at higher temperature,could inhibit the formation and deposition of sulfate on catalyst surface,decreasing O-depletion.However,the remarkable activity loss was found after the catalyst was presulfated with 0.02% SO2 at 300 ℃ over 1 h.The O2-is nearly completely consumed and O-decreased notably,both were converted into OIII（O2-2）.Probably K failed to suppress the sulfate formation and deposition at a lower temperature,thus accelerated the consumption of O2-and led to the extinction of oxygen source available,and restrained the catalyst activity.
出处
《中国稀土学报》
CAS
CSCD
北大核心
2010年第2期165-170,共6页
Journal of the Chinese Society of Rare Earths
基金
广东高校科技成果转化项目(cgzhzd0803)
广东省自然科学基金项目(8151009101000025)
广东省社会发展科技项目(2007B030102006)资助
