以碳黑为第二模板剂在氟离子体系中一步水热合成了多级结构MCM-22分子筛组装体(简称为MCM-22-FC).考察了碳黑和氟离子对MCM-22分子筛形貌和催化性能的影响.MCM-22-FC分子筛是由大量片状晶体交错生长形成的组装体结构,其中MCM-22的片层结构更薄,在其固有的微孔中存在的晶间孔呈现大孔和介孔的特征.MCM-22-FC负载Mo后得到的Mo/MCM-22-FC催化剂在甲烷无氧芳构化反应(MDA)中提高了苯收率和芳烃选择性,并且提高了催化剂的寿命.通过氨气程序升温脱附(NH3-TPD)表征,吡啶红外(Py-IR)表征,结合热重(TG)分析,得出的结论是Mo/MCM-22-FC在MDA中优越的催化性能是由于氟离子进入到分子筛骨架当中,形成具有拉电子效应的结构单元,从而提高了分子筛的Br(o)nsted酸量,较多的Br(o)nsted酸性位将更多的Mo物种迁移至分子筛孔道内部,形成更多的MoCx或MoOxCy活性物种以及更有利于大分子产物扩散的MCM-22薄片层的结构.少量过剩的Br(o)nsted酸性位在成型后保留在Mo/HMCM-22-FC催化剂活性中心抑制了积碳的形成,也有助于改善芳烃的选择性.
参考文献
| [1] | Wang L S;Tao L X;Xie M S;Xu G F Huang J S Xu Y D .[J].Catalysis Letters,1993,21:35. |
| [2] | Marczewski M;Marczewska H;Debowiak M .[J].Reaction Kinetics and Catalysis Letters,1995,55:207. |
| [3] | Cui Y B;Xu Y B;Lu J Y;Suzuki Y Zhang Z G .[J].Applied Catalysis A: General,2011,393:348. |
| [4] | Matus E V;Ismagilov I Z;Sukhova O B;Zaikovskii V I Tsikoza L T Ismagilov Z R Moulijn J A .[J].Industrial & Engineering Chemistry Research,2006,46:4063. |
| [5] | Ma D;Shu Y Y;Cheng M J;Xu Y D Bao X H .[J].Journal of Catalysis,2000,194:105. |
| [6] | Liu B S;Jiang L;Sun H;Au C T .[J].Applied Surface Science,2007,253:5092. |
| [7] | Bai J.;Liu SL.;Xie SJ.;Xu LY.;Lin LW. .Shape selectivity in methane dehydroaromatization over Mo/MCM-22 catalysts during a lifetime experiment[J].Catalysis Letters,2003(3/4):123-130. |
| [8] | Liu, L;Ma, D;Chen, HY;Zheng, H;Cheng, MJ;Xu, YD;Bao, XH .Methane dehydroaromatization on Mo/HMCM-22 catalysts: effect of SiO2/Al2O3 ratio of HMCM-22 zeolite supports[J].Catalysis Letters,2006(1/2):25-30. |
| [9] | Sun C Y;Yao S D;Shen W J;Lin L W .[J].Microporous and Mesoporous Materials,2009,122:48. |
| [10] | Xing H J;Zhang Y;Jia M J;Wu S J Wang H S Guan J Q Xu L Wu T H Kan Q B .[J].CATALYSIS COMMUNICATIONS,2008,9:234. |
| [11] | Chu N B;YangJ H;WangJ Q;Yu S X LuJ M Zhang Y Yin D H .[J].CATALYSIS COMMUNICATIONS,2010,11:513. |
| [12] | Gu L J;Ma D;Hu G;Wu J J Wang H X Sun C Y Yao S D Shen W J Bao X H .[J].Dalton Transactions,2010,39:9705. |
| [13] | Wang H X;Su L L;Zhuang J G;Tan D L Xu Y D Bao X H .[J].Journal of Physical Chemistry B,2003,107:12964. |
| [14] | Liu H M;Su L L;Wang H X;Shen W J Bao X H Xu Y D .[J].Applied Catalysis A: General,2002,236:263. |
| [15] | Xu YD.;Bao XH.;Lin LW. .Direct conversion of methane under nonoxidative conditions[J].Journal of Catalysis,2003(1/2):386-395. |
| [16] | Ma D;Wang D Z;Su L L;Shu Y Y Xu Y D Bao X H .[J].Journal of Catalysis,2002,208:260. |
| [17] | Liu H M;Li T;Tian B L;Xu Y D .[J].Applied Catalysis A: General,2001,213:103. |
| [18] | Liu H W;Shen W J;Bao X H;Xu Y D .[J].Applied Catalysis A: General,2005,295:79. |
| [19] | Bergeudd H;Jonsson M;Ngstr(o)m D;Malmstr(o)m E .[J].Journal of Molecular Catalysis A: Chemical,2009,305:69. |
| [20] | Xu M C;Wang W;Seiler M;Buchholz A Hunger M .[J].Journal of Physical Chemistry B,2002,106:3202. |
| [21] | Shayib, R.M.;George, N.C.;Seshadri, R.;Burton, A.W.;Zones, S.I.;Chmelka, B.F. .Structure-directing roles and interactions of fluoride and organocations with siliceous zeolite frameworks[J].Journal of the American Chemical Society,2011(46):18728-18741. |
| [22] | Liu X L;Rayon U;Tuel A .[J].Chemistry of Materials,2011,23:5052. |
| [23] | Meng X J;Nawaz F;Xiao F S .[J].NANO TODAY,2009,4:292. |
| [24] | Zhou J;Hua Z L;Liu Z C;Wu W Zhu Y Shi J L .[J].ACS Catalysis,2011,1:287. |
| [25] | Chu N B;Wang J Q;Zhang Y;Yang J H Lu J M Yin D H .[J].Chemistry of Materials,2010,22:2757. |
| [26] | Corma A;Corell C;Pérez-Pariente J .[J].ZEOLITES,1995,15:2. |
| [27] | Lindner T;Lechert H .[J].ZEOLITES,1994,14:582. |
| [28] | Villaescusa L A;Wheatley P S;Bull I;Lightfoot P Morris R E .[J].Journal of the American Chemical Society,2001,123:8797. |
| [29] | Shu Y Y;Ma D;Xu L Y;Xu Y D Bao X H .[J].Catalysis Letters,2000,70:67. |
| [30] | Ren D M;Wang X S;Li G;Cheng X J Long H Y Chen L D .[J].Journal of Natural Gas Chemistry,2010,19:646. |
| [31] | Ma D;Zhang W P;Shu Y Y;Liu X M Xu Y D Bao X H .[J].Catalysis Letters,2000,66:155. |
| [32] | Zheng S R;Heydenrych H R;Jentys A;Lercher J A .[J].Journal of Physical Chemistry B,2002,106:9552. |
| [33] | Musilová-Pavla(c)ková Z;Zones S I;(C)ejka J .[J].Topics in Catalysis,2010,53:273. |
| [34] | Serrano, D.P.;García, R.A.;Vicente, G.;Linares, M.;Procházková, D.;?ejka, J. .Acidic and catalytic properties of hierarchical zeolites and hybrid ordered mesoporous materials assembled from MFI protozeolitic units[J].Journal of Catalysis,2011(2):366-380. |
| [35] | Youngman RE;Sen S .Structural role of fluorine in amorphous silica[J].Journal of Non-Crystalline Solids: A Journal Devoted to Oxide, Halide, Chalcogenide and Metallic Glasses, Amorphous Semiconductors, Non-Crystalline Films, Glass-Ceramics and Glassy Composites,2004(0):10-15. |
| [36] | Louis B;Kiwi-Minsker L .[J].Microporous and Mesoporous Materials,2004,74:171. |
| [37] | Goa Y;Wu P;Tatsumi T .[J].Journal of Physical Chemistry B,2004,108:4242. |
| [38] | Fang X Q;Wang Q;Zheng A M;Liu Y M Wang Y N Deng X J Wu H H Deng F He M Y Wu P .[J].Catalysis Science & Technology,2012,2:2433. |
| [39] | Borry R WⅢ;Kim Y H;Huffsmith A;Reimer J A Iglesia E .[J].Journal of Physical Chemistry B,1999,103:5787. |
| [40] | Li W.;Borry RW.;Iglesia E.;Meitzner GD. .Raman and X-ray absorption studies of Mo species in Mo/H-ZSM5 catalysts for non-oxidative CH4 reactions[J].Journal of Catalysis,2000(2):373-383. |
| [41] | Ma D;Lu Y;Su L L;Xu Z S Tian Z J Xu Y D Lin L W Bao X H .[J].Journal of Physical Chemistry B,2002,106:8524. |
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