采用不同方法表征了硅铝比(SiO2/Al2O3)为33、266和487的质子型ZSM-5分子筛，并研究了ZSM-5分子筛作为助催化剂在渣油裂解中的应用。与USY分子筛基催化剂混合后，在固定流化床上，评价了ZSM-5分子筛助催化剂的催化裂化性能。研究发现，提高ZSM-5分子筛硅铝比，可以有效抑制混合催化剂对汽油烯烃的裂解，从而避免了汽油烷烃的大量损失。加入ZSM-5助催化剂后，伴随着液化气(LPG)产率的增加，异丁烷和异戊烷产率增加，这可能是由USY基催化剂和ZSM-5助催化剂的综合效应引起的。汽油烷烃和芳烃含量的变化，引起了汽油辛烷值的增加。高硅铝比ZSM-5分子筛(硅铝比为266和487)不仅可以显著改善汽油的辛烷值，而且有效避免了汽油的大量损失。催化汽油辛烷值的改善主要是由于高硅铝比ZSM-5分子筛具有适宜的芳构化和异构化活性，这些变化主要源于高硅铝比ZSM-5分子筛小的孔道直径和适宜的酸性。
Three proton-type ZSM-5 zeolites with different SiO2/Al2O3 ratios (SARs) of 33, 266, and 487 were characterized and examined as fluid catalytic cracking catalyst additives for residue oil cracking. The catalytic performance of the ZSM-5 additives was evaluated using an ultra-stable Y-zeolite (USY)-based fluid catalytic cracking catalyst in a fixed fluid bed unit. As observed, the cracking of primary olefins over the hybrid catalysts consisting of USY-based catalyst and ZSM-5 additive was considerably inhibited by increasing the SAR of the ZSM-5 zeolite, thus avoiding substantial loss of gasoline paraffins. The introduction of ZSM-5 additives led to higher liquid petroleum gas yields as well as higher isobutane and isopentane yields. The improved yields were attributed to the com-bined effects of the ZSM-5 additives and USY-based catalyst. The variations of gasoline paraffins and aromatics both accounted for the enhancement in the octane number values. The use of ZSM-5 with higher SARs (266 and 487) led to an enhancement in the octane number with minimal loss of gaso-line. This enhancement was mainly attributed to the moderate aromatization and isomerization reactivity of the ZSM-5 additives that mainly originated from their relatively small pores and suita-ble acidic properties with higher SARs.
参考文献
| [1] | Argauer R J;Landolt G R .[P].US Patent 3 702 886,1972. |
| [2] | Csicsery S M .[J].ZEOLITES,1984,4:202. |
| [3] | Corma A .[J].Studies in surface science and catalysis,1989,49:49. |
| [4] | Degnan T F;Chitnis G K;Schipper P H .[J].Microporous and Mesoporous Materials,2000,35-36:245. |
| [5] | Buchanan J S;Olson D H;Schramm S E .[J].Applied Catalysis A:General,2001,220:223. |
| [6] | Gao X H;Tang Z C;Zhang H T;Ji D Lu G X Wang Z F Tan Z G .[J].Journal of Molecular Catalysis A:Chemical,2010,325:36. |
| [7] | Kuehler C W.Fluid Cracking Catalysts(Chemical Industries 74)[M].CRC Press,1998:31. |
| [8] | Arandes J M;Torre I;Azkoiti M J;Erena J Olazar M Bilbao J .[J].Energy and Fuels,2009,23:4215. |
| [9] | Reddy, J.K.;Motokura, K.;Koyama, T.-R.;Miyaji, A.;Baba, T..Effect of morphology and particle size of ZSM-5 on catalytic performance for ethylene conversion and heptane cracking[J].Journal of Catalysis,2012:53-61. |
| [10] | Cundy C S;Henty M S;Plaisted R J .[J].ZEOLITES,1995,15:342. |
| [11] | Liu C Y;Gu W Y;Kong D J;Guo H C .[J].Microporous and Mesoporous Materials,2014,183:30. |
| [12] | Liu C Y;Kong D J;Guo H C .[J].Microporous and Mesoporous Materials,2014,193:61. |
| [13] | Weitkamp J;Puppe L.Catalysis and zeolites:fundamentals and applications[M].New York:Springer-Verlag,1999:224. |
| [14] | 周健,刘志成,李丽媛,王仰东,高焕新,杨为民,谢在库,唐颐.多级孔ZSM-5分子筛：丰富的外表面酸中心和良好的二甲苯异构化催化性能[J].催化学报,2013(07):1429-1433. |
| [15] | 张培青,徐金光,王祥生,郭洪臣.纳米HZSM-5催化剂催化C8直链烃转化的性能[J].催化学报,2005(03):216-222. |
| [16] | Buchanan JS.;Haag WO.;Santiesteban JG. .MECHANISTIC CONSIDERATIONS IN ACID-CATALYZED CRACKING OF OLEFINS[J].Journal of Catalysis,1996(1):279-287. |
| [17] | Buchanan J S .[J].Catalysis Today,2000,55:207. |
| [18] | Buchanan J S .[J].Applied Catalysis,1991,74:83. |
| [19] | Shan Z C;Wang H;Meng X J;Liu S Y Wang L Wang C Y Li F Lewis J P Xiao F S .[J].Chemistry Communications,2011,47:1048. |
| [20] | Yang G J;Wei Y X;Xu S T;Chen J R Li J Z Liu Z M Yu J H Xu R R .[J].J Phys Chem C,2013,117:8214. |
| [21] | Madon R J .[J].Journal of Catalysis,1991,129:275. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%