采用 HCl 溶液和/或水热处理 HEU-1分子筛,利用 X 射线衍射、N2吸附-脱附、X 射线荧光光谱、NH3程序升温脱附、吡啶吸附傅里叶变换红外光谱和铝固体核磁共振等对脱铝处理的 HEU-1分子筛进行了表征,并考察了脱铝 HEU-1分子筛上正己烷的催化裂解性能.结果表明,采用 HCl 溶液处理 HEU-1分子筛,能有效脱除非骨架铝,可调变样品的弱酸中心;而水热处理 HEU-1分子筛,能有效脱除骨架铝,可调变样品的强酸中心.水热处理和 HCl 溶液处理有效结合可以达到同时调变HEU-1分子筛的酸类型和酸密度的目的.脱铝 HEU-1分子筛上正己烷催化裂解反应结果表明,氢转移反应被明显抑制,丙烯选择性提高.600°C 水热处理后再用 HCl 溶液处理的 HEU-1分子筛于625°C 反应时丙烯选择性由未改性的21.9%提高到35.2%,活性稳定性也由不足10 h 提高到40 h.
A series of modified HEU-1 zeolites were prepared using hydrochloric acid treatment, hydrothermal treatment, and a combination of these. The parent and modified HEU-1 zeolites were characterized by X-ray diffraction, N2 adsorption-desorption isotherms, X-ray fluo-rescence, temperature-programmed desorption of ammonia, Fourier-transform infrared spectroscopy of adsorbed pyridine, and 27Al solid-state magic-angle spinning nuclear magnetic resonance techniques. The catalytic cracking performances of the modified HEU-1 zeo-lites were evaluated on a fixed-bed microreactor at 625 °C, atmospheric pressure, and an n-hexane weight hourly space velocity of 2.0 h?1. The results showed that extra-framework alumina could be removed by directly treating with hydrochloric acid, and framework alumina could be removed by hydrothermal treatment. Acidity characterization showed that the weak acid sites of HEU-1 zeolites could be adjusted using acid treatment, and the number of strong acid sites could be reduced using hydrothermal treatment. The framework nSi:nAl ratio was improved by using a combination of hydrothermal treatment and acid leaching. The acidities of the HEU-1 zeolites were adjusted and both the mesopore volume and external surface area were enhanced. In n-hexane cracking reactions, the dealuminated HEU-1 zeolite obtained by hydrothermal treatment for 4 h at 600 °C and then washing with hydrochloric acid exhibited the highest propylene production as a result of suppression of the hydrogen transfer reaction. At 625 °C, the selectivity for propylene on HEU-1(HT4-HCl) increased to 35.2% from 21.9%, and the lifetime of HEU-1(HT4-HCl) was also prolonged from not more than 10 to 40 h.
参考文献
| [1] | Casci J L;Lowe B M;Whittam T V .[P].EP 0042226,1981. |
| [2] | Briscoe N A;Johnson D W;Shannon M D;Kokotailo G T McCusker L B .[J].Zeolites,1988,8:74. |
| [3] | Peral I;Jones C Y;Varkey S P;Lobo R F .[J].Microporous and Mesoporous Materials,2004,71:125. |
| [4] | Moreau, F;Moreau, P;Gnep, NS;Magnoux, P;Lacombe, S;Guisnet, M .Ethylbenzene isomerization over bifunctional platinum alumina-EUO catalysts: Location of the active sites[J].Microporous and Mesoporous Materials,2006(1/3):327-338. |
| [5] | Alario F;Joly J-F;Magne-Drisch J;Merlen E, Benazzi E, Lacombe S .[P].US 6337427B1,2002. |
| [6] | Joly J-F;Coupard V;Magne-Drisch J;Alario F, Merlen E, Lacombe S, Benazzi E .[P].US 6147269,2000. |
| [7] | Teketel S;Skistad W;Benard S;Olsbye U Lillerud K P Beato P Svelle S .[J].ACS Catal,2011,2:26. |
| [8] | Abrevaya H .[J].Studies in Surface Science and Catalysis,2007,170:1244. |
| [9] | Jolly S;Saussey J;Bettahar M M;Lavalley J C Benazzi E .[J].Applied Catalysis A:General,1997,156:71. |
| [10] | Corma A;Melo F V;Sauvanaud L;Ortega F .[J].Catalysis Today,2005,107-108:699. |
| [11] | Kotrel S;Kn?zinger H;Gates B C .[J].Microporous Mesopor-ous Mater,2000,35-36:11. |
| [12] | Corma A;Mengual J;Miguel P J .[J].Applied Catalysis A:General,2012,421:121. |
| [13] | Teimouri Sendesi S M;Towfighi J;Keyvanloo K .[J].Catalysis Communications,2012,27:114. |
| [14] | 冯利利;齐兴义;李征;朱岳麟 李星国 .[J].催化学报,2012,30:340. |
| [15] | Lee K-H;Ha B-H .[J].Microporous and Mesoporous Materials,1998,23:211. |
| [16] | Triantafillidis C S;Vlessidis A G;Nalbandian L;Evmiridis N P .[J].Microporous and Mesoporous Materials,2001,47:369. |
| [17] | Wei R C;Li C Y;Yang C H;Shan H H .[J].Journal of Natural Gas Chemistry,2011,20:261. |
| [18] | Jin L J;Hu H Q;Zhu S W;Ma B .[J].Catalysis Today,2010,149:207. |
| [19] | 李强,窦涛,霍全,徐庆虎,巩雁军,潘惠芳.不同硅铝比β沸石的理化性质及烃类催化裂化活性[J].物理化学学报,2008(07):1192-1198. |
| [20] | Müller M;Harvey G;Prins R .[J].Microporous and Mesoporous Materials,2000,34:135. |
| [21] | Marques J P;Gener I;Lopes J M;Ribeiro F R Guisnet M .[J].Applied Catalysis A:General,2006,301:96. |
| [22] | Fan Y;Bao X;Lin X;Shi G Liu H .[J].Journal of Physical Chemistry B,2006,110:15411. |
| [23] | 龙化云,王祥生,孙万付,刘海鸥,程晓晶.脱铝方法对纳米HZSM-5物化性能的影响[J].石油学报（石油加工）,2009(03):332-338. |
| [24] | 张培青;王祥生;郭洪臣;徐舟波 赵乐平 胡永康 .[J].催化学报,2003,24:904. |
| [25] | Zhao X;Guo X;Wang X .[J].Fuel Processing Technology,2007,88:237. |
| [26] | Xu Q H;Gong Y J;Xu W J;Xu J Deng F Dou T .[J].Journal of Colloid and Interface Science,2011,358:252. |
| [27] | Ray P K;Montague P E .[J].Journal of Applied Polymer Science,1977,21:1267. |
| [28] | Xu B;Sievers C;Hong S B;Prins R van Bokhoven J A .[J].Journal of Catalysis,2006,244:163. |
| [29] | Li X;Prins R;van Bokhoven J A .[J].Journal of Catalysis,2009,262:257. |
| [30] | 毛东森,郭强胜,孟涛,卢冠忠.水热处理对纳米HZSM-5分子筛酸性及催化甲醇制丙烯反应性能的影响[J].物理化学学报,2010(02):338-344. |
| [31] | Costa C.;Lopes JM.;Lemos F.;Ribeiro FR.;Dzikh IP. .Activity-acidity relationship in zeolite ZSM-5. Application of Bronsted-type equations[J].Journal of molecular catalysis, A. Chemical,2000(1/2):193-201. |
| [32] | Sano T;Uno Y;Wang Z B;Ahn C H Soga K .[J].Microporous and Mesoporous Materials,1999,31:89. |
| [33] | Barzetti T;Selli E;Moscotti D;Forni L .[J].Journal of the Chemical Society,Faraday Transactions,1996,92:1401. |
| [34] | Emeis C A .[J].Journal of Catalysis,1993,141:347. |
| [35] | Inagaki, S;Takechi, K;Kubota, Y .Selective formation of propylene by hexane cracking over MCM-68 zeolite catalyst[J].Chemical communications,2010(15):2662-2664. |
| [36] | Bortnovsky O;Sazama P;Wichterlova B .Cracking of pentenes to C-2-C-4 light olefins over zeolites and zeotypes - Role of topology and acid site strength and concentration[J].Applied Catalysis, A. General: An International Journal Devoted to Catalytic Science and Its Applications,2005(2):203-213. |
| [37] | Lukyanov D B;Shtral V I;Khadzhiev S N .[J].Journal of Catalysis,1994,146:87. |
| [38] | Riekerti L;Zhou J Q .[J].Journal of Catalysis,1992,137:437. |
| [39] | 朱向学,宋月芹,李宏冰,刘盛林,孙新德,徐龙伢.丁烯催化裂解制丙烯/乙烯反应的热力学研究[J].催化学报,2005(02):111-117. |
| [40] | Corma A;González-Alfaro V;Orchillés A V .[J].Applied Catalysis A:General,1999,187:245. |
| [41] | Corma A;Planelles J;Sánchez-Marín J;Tomás F .[J].Journal of Catalysis,1985,93:30. |
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