La_(1-x)Sr_xFeO_3钙钛矿型氧化物中的晶格氧用于甲烷部分氧化制合成气  

La_(1-x)Sr_xFeO_3 perovskites as oxygen carriers for the partial oxidation of methane to syngas

作　　者：赵坤[1,2] 何方[1] 黄振[1] 郑安庆[1] 李海滨[1] 赵增立[1] 

机构地区：[1]中国科学院广州能源研究所中国科学院可再生能源与天然气水合物重点实验室,广东广州510640 [2]中国科学院大学,北京100049

出　　处：《催化学报》2014年第7期1196-1205,共10页

基　　金：国家自然科学基金(51076154);"十二五"国家科技支撑计划项目(2011BAD15B05)~~

摘　　要：采用燃烧法制备了Sr掺杂钙钛矿型氧化物La1-xSrxFeO3(x=0,0.3,0.5,0.9)载氧体,对载氧体分别进行X射线衍射、扫描电镜和H2程序升温还原反应表征,在热重循环装置和固定床反应装置上考察甲烷与载氧体晶格氧的部分氧化反应.结果表明,La1-xSrxFeO3氧化物中的晶格氧适用于甲烷部分氧化制合成气,晶格氧的得失是一个可逆过程,Sr的掺杂提高了载氧体的供氧能力,5次循环后载氧体得失晶格氧的能力没有明显的衰减.从甲烷转化率、n(H2)/n(CO)比以及H2和CO的选择性等方面来考虑,x=0.3–0.5比较理想,甲烷转化率维持在70%左右,气体产物中n(H2)/n(CO)约为2,CH4没有发生明显的裂解.We prepared perovskite-type oxides La1-xSrxFeO3 （x = 0, 0.3, 0.5, 0.9） by a combustion method and used these as oxygen carriers for the partial oxidation of methane. X-ray diffration, scanning electron microscopy and H2 temperature-programmed reduction techniques were used to characterize the samples. Their reduction and oxidation activities were investigated using a thermogravimetric analysis reactor and fixed-bed reaction equipment, respectively. The results showed that the lattice oxygen in La1-xSrxFeO3 was suitable for the partial oxidation of methane to produce syngas. Their capacity to provide oxygen was enhanced by the partial substitution of La3＋ by Sr2＋ and the synthesized materials have good regenerability. The optimal degree of Sr substitution was found to be x =0.3-0.5 for La1-xSrxFeO3 with regard to reactivity, selectivity, and oxygen-donating ability. CH4 con-version was higher than 70%, and the n（H2）/n（CO） ratio remained about 2：1 and no obvious decomposition of CH4 occurred.

关 键 词：钙钛矿 晶格氧 热重循环 部分氧化 合成气 

分 类 号：TE665.3[石油与天然气工程—油气加工工程]