|
OALib Journal期刊
ISSN: 2333-9721
费用：99美元
|
|
|
|
负载型V2O5/TiO2催化剂表面分散状态和性质对氨选择性催化还原NO性能的影响
DOI: 10.1016/S1872-2067(11)60365-3, PP. 933-940
Keywords: 钒氧物种,分散状态,选择性催化还原,B酸位,可还原性,氮氧化物
Abstract:
？采用多种物理化学手段研究了不同负载量V2O5/TiO2催化剂的VOx物种分散状态、表面酸性、可还原性及其选择性催化还原(SCR)NO性能.结果表明,V2O5在锐钛矿TiO2表面的实测单层分散容量约为1.14mmolV/100m2TiO2,与“嵌入模型”的估算值相符,表明分散态的钒离子应键合在TiO2表面的八面体空位上.随着V2O5负载量的增加,V2O5/TiO2催化剂上NO转化频率(TOF)先急剧增加,至0.70mmolV/100m2TiO2(略超过分散容量的一半)时达到极大(约8.3×10-3s-1),然后又急剧下降;同时,孤立VOx物种可能倾向于分散在相邻的八面体空位上,且通过V–O–V化学键相连形成聚合的VOx物种,V–O–V键所占比例增加而V–O–Ti键所占比例减小,催化剂表面单位钒离子的Br？nsted酸中心量增加,故催化剂的TOF急剧增加.随着负载量进一步增加,虽然催化剂表面单位钒离子的Br？nsted酸中心量仍缓慢增加,但V–O–Ti键所占比例减少,导致钒离子的可还原性下降,另外,分散容量以上时晶相V2O5的形成也导致钒离子表面利用率下降,从而导致催化剂的TOF下降.桥式Br？nsted酸位(V–O(H)–V)也是SCR反应活性中心之一,不同负载量V2O5/TiO2催化剂上SCR活性与表面VOx物种的分散状态、表面酸性和钒离子可还原性密切相关.
| [1] | Tang F S, Xu B L, Shi H H, Qiu J H, Fan Y N. Appl Catal B, 2010, 94: 71
|
| [2] | 刘清雅, 刘振宇, 李成岳. 催化学报(Liu Q Y, Liu Zh Y, Li Ch Y. Chin J Catal), 2006, 27: 636
|
| [3] | Bosch H, Kip B J, van Ommen J G, Gellings P J. J Chem Soc, Faraday Trans 1, 1984, 80: 2479
|
| [4] | Busca G, Centi G, Marchetti L, Trifiro F. Langmuir, 1986, 2: 568
|
| [5] | Gheorghe C, Gee B. Chem Mater, 2000, 12: 682
|
| [6] | Forzatti P. Appl Catal A, 2001, 222: 221
|
| [7] | Bond G C, Tahir S F. Appl Catal, 1991, 71: 1
|
| [8] | Ba？ares M A, Wachs I E. J Raman Spectrosc, 2002, 33: 359
|
| [9] | Grzybowska-Swierkosz B. Appl Catal A, 1997, 157: 263
|
| [10] | Wachs I E, Weckhuysen B M. Appl Catal A, 1997, 157: 67
|
| [11] | Went G T, Leu L J, Bell A T. J Catal, 1992, 134: 479
|
| [12] | Went G T, Leu L J, Rosin R R, Bell A T. J Catal, 1992, 134: 492
|
| [13] | Baiker A, Handy B, Nickl J, Schraml-Marth M, Wokaun A. Catal Lett, 1992, 14: 89
|
| [14] | Lietti L, Forzatti P. J Catal, 1994, 147: 241
|
| [15] | Tops？e N-Y, Tops？e H, Dumesic J A. J Catal, 1995, 151: 226
|
| [16] | Marshneva V I, Slavinskaya E M, Kalinkina O V, Odegova G V, Moroz E M, Lavrova G V, Salanov A N. J Catal, 1995, 155: 171
|
| [17] | Alemany L J, Lietti L, Ferlazzo N, Forzatti P, Busca G, Giamello E, Bregani F. J Catal, 1995, 155: 117
|
| [18] | Wachs I E, Deo G, Weckhuysen B M, Andreini A, Vuurman M A, de Boer M, Amiridis M D. J Catal, 1996, 161: 211
|
| [19] | Reiche M A, Hug P, Baiker A. J Catal, 2000, 192: 400
|
| [20] | Amiridis M D, Wachs I E, Deo G, Jehng J M, Kim D S. J Catal, 1996, 161: 247
|
| [21] | Ni Z M, Chen A M, Fang C P, Wang L G, Yu W H. J Phys Chem Solids, 2009, 70: 632
|
| [22] | Xie Y C, Tang Y Q. Adv Catal, 1990, 37: 1
|
| [23] | Deo G, Wachs I E. J Catal, 1994, 146: 323
|
| [24] | Wachs I E. Catal Today, 1996, 27: 437
|
| [25] | Primet M, Pichat P, Mathieu M V. J Phys Chem, 1971, 75: 1216
|
| [26] | Xu B L, Fan Y N, Liu L, Lin M, Chen Y. Sci China, Ser B, 2002, 45: 407
|
| [27] | Chen Y, Zhang L F. Catal Lett, 1992, 12: 51
|
| [28] | Dong L, Chen Y. Chin J Inorg Chem, 2000, 16: 250
|
| [29] | Mutin P H, Popa A F, Vioux A, Delahay G, Coq B. Appl Catal B, 2006, 69: 49
|
| [30] | Giakoumelou I, Fountzoula C, Kordulis C, Boghosian S. J Catal, 2006, 239: 1
|
| [31] | Ramis G, Busca G, Bregani F, Forzatti P. Appl Catal, 1990, 64: 259
|
| [32] | Ramis G, Yi L, Busca G. Catal Today, 1996, 28: 373
|
| [33] | Tops？e N-Y. J Catal, 1991, 128: 499
|
| [34] | Busca G, Lietti L, Ramis G, Berti F. Appl Catal B, 1998, 18: 1
|
| [35] | Tops？e N-Y, Dumesic J A, Tops？e H. J Catal, 1995, 151: 241.
|
| [36] | Went G T, Oyama S T, Bell A T. J Phys Chem, 1990, 94: 4240
|
| [37] | Miyata H, Fujii K, Ono T. J Chem Soc, Faraday Trans 1, 1988, 84: 3121
|
| [38] | Ozkan U S, Cai Y P, Kumthekar M M. Appl Catal A, 1993, 96: 365
|
| [39] | Gasior M, Haber J, Machej T, Czeppe T. J Mol Catal, 1988, 43: 359
|
Full-Text
|
|
Contact Us
service@oalib.com QQ:3279437679 
WhatsApp +8615387084133
|
|
