Stability Enhancement of ZSM-5 zeolite in Olefin Aromatization by Alkali Treatment. Comparison of Medium

摘要/Abstract

摘要： ZSM-5 zeolites with a SiO2/Al2O3 ratio of 40 were synthesized by a hydrothermal method, and treated by 0.3 M tetrapropyl ammonium hydroxide (TPAOH) and 0.3 M sodium hydroxide (NaOH) separately to create hollow structures. The synthesized ZSM-5 zeolite and treated ZSM-5 zeolites were evaluated for aromatization of 1-hexene in a continuous flow reactor. The prepared ZSM-5 zeolites were characterized by XRD, SEM, TEM, NMR, XPS and other analyses. The results showed that the alkali treatment formed mesopores and hollow structures in the ZSM-5 crystals without destroying the topological structure. The acid amount of ZSM-5 zeolite was also increased after alkali treatment. Compared with the ZSM-5 zeolite treated by TPAOH, the ZSM-5 zeolite treated by NaOH had more mesopores and a higher total acid amount but a lower strong acid amount, resulting in higher aromatics yields and catalytic stability in 1-hexene aromatization. The characterization of spent ZSM-5 zeolites suggested that the spent treated ZSM-5 zeolites contained less coke, leading to a smaller reduction of micropore surface area and volume than in the spent parent ZSM-5, which contributed to the stability enhancement.

关键词: ZSM-5, post treatment, hollow structure, stability enhancement, aromatization

Abstract: ZSM-5 zeolites with a SiO2/Al2O3 ratio of 40 were synthesized by a hydrothermal method, and treated by 0.3 M tetrapropyl ammonium hydroxide (TPAOH) and 0.3 M sodium hydroxide (NaOH) separately to create hollow structures. The synthesized ZSM-5 zeolite and treated ZSM-5 zeolites were evaluated for aromatization of 1-hexene in a continuous flow reactor. The prepared ZSM-5 zeolites were characterized by XRD, SEM, TEM, NMR, XPS and other analyses. The results showed that the alkali treatment formed mesopores and hollow structures in the ZSM-5 crystals without destroying the topological structure. The acid amount of ZSM-5 zeolite was also increased after alkali treatment. Compared with the ZSM-5 zeolite treated by TPAOH, the ZSM-5 zeolite treated by NaOH had more mesopores and a higher total acid amount but a lower strong acid amount, resulting in higher aromatics yields and catalytic stability in 1-hexene aromatization. The characterization of spent ZSM-5 zeolites suggested that the spent treated ZSM-5 zeolites contained less coke, leading to a smaller reduction of micropore surface area and volume than in the spent parent ZSM-5, which contributed to the stability enhancement.

陈小博安志远朱超闫昊刘熠斌冯翔金鑫杨朝合. Stability Enhancement of ZSM-5 zeolite in Olefin Aromatization by Alkali Treatment. Comparison of Medium[J]. , 2020, 22(4): 63-72.

Xiao-Bo CHEN Zhiyuan An Liu Yibin Yang Chaohe. Stability Enhancement of ZSM-5 zeolite in Olefin Aromatization by Alkali Treatment. Comparison of Medium[J]. , 2020, 22(4): 63-72.

参考文献

[1] Sadeghbeigi R. Fluid Catalytic Cracking Handbook (Third Edition) [M]. Butterworth-Heinemann: Oxford, 2012 [2] Fang Y J, Su X F, Bai X F, et al. Aromatization over nanosized Ga-containing ZSM-5 zeolites prepared by different methods: Effect of acidity of active Ga species on the catalytic performance [J]. Journal of Energy Chemistry, 2017, 26 (4): 768-775 [3] Chinese Standard: Gasoline for Motor Vehicles (GB 17930-2016) [S], 2016 (in Chinese) [4] Worldwide Fuel Charter. (Fifth Edition) [S]. 2013 [5] Ouyang F S, Xu P, Zhao X H, et al. Effect of Operation conditions on the composition and octane number of gasoline in the process of reducing the content of olefins in fluid catalytic cracking (FCC) gasoline [J]. Energy & Fuels, 2010, 24 (1): 475-482 [6] Zhao X B, Guo X W, Wang X S. Effect of hydrothermal treatment temperature on FCC gasoline upgrading properties of the modified nanoscale ZSM-5 catalyst [J]. Fuel Processing Technology, 2007, 88 (3): 237-241 [7] Fan Y, Lei D, Shi G, et al. Synthesis of ZSM-5/SAPO-11 composite and its application in FCC gasoline hydro-upgrading catalyst [J]. Catalysis Today, 2006, 114 (4): 388-396 [8] Fan Y, Lin X Y, Shi G, et al. Realumination of dealuminated HZSM-5 zeolite by citric acid treatment and its application in preparing FCC gasoline hydro-upgrading catalyst [J]. Microporous and Mesoporous Materials, 2007, 98 (1-3): 174-181 [9] Lin X Y, Fan Y, Liu Z H, et al. A novel method for enhancing on-stream stability of fluid catalytic cracking (FCC) gasoline hydro-upgrading catalyst: Post-treatment of HZSM-5 zeolite by combined steaming and citric acid leaching [J]. Catalysis Today, 2007, 125 (3-4): 185-191 [10] Liu S, You H. Aromatization of Yanhua FCC gasoline [J]. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2015, 37 (11): 1180-1185 [11] Fan Y, Bao X J, Shi G, et al. Olefin reduction of FCC gasoline via hydroisomerization aromatization over modified HMOR/HZSM-5/Hβ composite carriers [J]. Applied Catalysis A: General, 2004, 275 (1-2): 61-71 [12] Fan Y, Bao X J, Shi G. Hβ/HZSM-5 composite carrier supported catalysts for olefins reduction of FCC gasoline via hydroisomerization and aromatization [J]. Catalysis Letters, 2005, 105 (1): 67-75 [13] Zhao L, Zhu J, Wang H Y, et al. Aromatization of FCC gasoline over modified HZSM-5 catalyst [J]. Petroleum Science and Technology, 2007, 25 (5): 577-584 [14] Wang P, Shen B J, Gao J S. Synthesis of MAZ/ZSM-5 composite zeolite and its catalytic performance in FCC gasoline aromatization [J]. Catalysis Communications, 2007, 8 (7): 1161-1166 [15] Wang P, Shen B J, Gao J S. Synthesis of ZSM-5 zeolite from expanded perlite and its catalytic performance in FCC gasoline aromatization [J]. Catalysis Today, 2007, 125 (3-4): 155-162 [16] Long H Y, Jin F Y, Xiong, G, et al. Effect of lanthanum and phosphorus on the aromatization activity of Zn/ZSM-5 in FCC gasoline upgrading [J]. Microporous and Mesoporous Materials, 2014, 198: 29-34 [17] Rihko L K, Krause A O I. Etherification of FCC light gasoline with methanol [J]. Industrial & Engineering Chemistry Research, 1996, 35 (8): 2500-2507 [18] Hu T F, Chen J P, Wang H Y, et al. Influence of shaped and modified Hβ zeolite on etherification of FCC light gasoline [J]. Microporous and Mesoporous Materials, 2006, 94 (1-3): 283-287 [19] Su X F, Wang G L, Bai X F, et al. Synthesis of nanosized HZSM-5 zeolites isomorphously substituted by gallium and their catalytic performance in the aromatization [J]. Chemical Engineering Journal, 2016, 293: 365-375 [20] Yang H L, Ma C Y, Li Y, et al. Synthesis, characterization and evaluations of the Ag/ZSM-5 for ethylene oxidation at room temperature: Investigating the effect of water and deactivation [J]. Chemical Engineering Journal, 2018, 347: 808-818 [21] Sundberg J, Standl S, von Aretin T, et al. Optimal process for catalytic cracking of higher olefins on ZSM-5 [J]. Chemical Engineering Journal, 2018, 348: 84-94 [22] Li Y N, Liu S L, Zhang Z K, et al. Aromatization and isomerization of 1-hexene over alkali-treated HZSM-5 zeolites: Improved reaction stability [J]. Applied Catalysis A: General, 2008, 338 (1-2): 100-113 [23] Groen J C, Zhu W D, Brouwer S, et al. Direct demonstration of enhanced diffusion in mesoporous ZSM-5 zeolite obtained via controlled desilication [J]. Journal of the American Chemical Society, 2007, 129 (2): 355-360 [24] Song Y Q, Zhu X X, Song Y, et al. An effective method to enhance the stability on-stream of butene aromatization: Post-treatment of ZSM-5 by alkali solution of sodium hydroxide [J]. Applied Catalysis A: General, 2006, 302 (1): 69-77 [25] Kim Y H, Lee K H, Nam C M, et al. Formation of hierarchical pore structures in Zn/ZSM-5 to improve the catalyst stability in the aromatization of branched olefins [J]. ChemCatChem, 2012, 4 (8): 1143-1153 [26] Li Y N, Liu S L, Xie S J, et al. Promoted metal utilization capacity of alkali-treated zeolite: Preparation of Zn/ZSM-5 and its application in 1-hexene aromatization [J]. Applied Catalysis A: General, 2009, 360 (1): 8-16 [27] Na K S, Choi M K, Ryoo R. Recent advances in the synthesis of hierarchically nanoporous zeolites [J]. Microporous and Mesoporous Materials, 2013, 166: 3-19 [28] Yang X Y, Chen L H, Li Y, et al. Hierarchically porous materials: synthesis strategies and structure design [J]. Chemical Society Reviews, 2017, 46 (2): 481-558 [29] Parlett C M A, Wilson K, Lee A F. Hierarchical porous materials: catalytic applications [J]. Chemical Society Reviews, 2013, 42 (9): 3876-3893 [30] Choi S W, Park J Y, Lee C M, et al. Synthesis of highly crystalline hollow TiO2 fibers using atomic layer deposition on polymer templates [J]. Journal of the American Ceramic Society, 2011, 94 (7): 1974-1977 [31] Groen J C, Bach T, Paulaime-van Donk A M, et al. Creation of hollow zeolite architectures by controlled desilication of Al-zoned ZSM-5 crystals [J]. Journal of the American Chemical Society, 2005, 127 (31): 10792-10793 [32] Groen J C, Jansen J C, Moulijn J A, et al. Optimal aluminum-assisted mesoporosity development in MFI Zeolites by desilication [J]. The Journal of Physical Chemistry B, 2004, 108 (35): 13062-13065 [33] Zhou F, Gao Y, Wu G, et al. Improved catalytic performance and decreased coke formation in post-treated ZSM-5 zeolites for methanol aromatization [J]. Microporous and Mesoporous Materials, 2017, 240: 96-107 [34] Fodor D, Pacosova L, Krumeich F, et al. Facile synthesis of nano-sized hollow single crystal zeolites under mild conditions [J]. Chemical Communication, 2014, 50 (1): 76-78 [35] Fodor D, Krumeich F, Hauert R, et al. Differences between individual ZSM-5 crystals in forming hollow single crystals and mesopores during base leaching [J]. Chemistry-A European Journal, 2015, 21 (16): 6272-6277 [36] Fodor D, Ishikawa T, Krumeich F, et al. Synthesis of single crystal nanoreactor materials with multiple catalytic functions by incipient wetness impregnation and ion exchange [J]. Advanced Materials, 2015, 27 (11): 1919-1923 [37] Mei C S, Liu Z C, Wen P Y, et al. Regular HZSM-5 microboxes prepared via a mild alkaline treatment [J]. Journal of Materials Chemistry, 2008, 18 (29): 3496-3500 [38] Wang Y R, Lin M, Tuel A. Hollow TS-1 crystals formed via a dissolution–recrystallization process [J]. Microporous and Mesoporous Materials, 2007, 102 (1-3): 80-85 [39] Dai C Y, Zhang A F, Li L L, et al. Synthesis of hollow nanocubes and aacroporous monoliths of silicalite-1 by alkaline treatment [J]. Chemistry of Materials, 2013, 25 (21): 4197-4205 [40] Dai C Y, Zhang A F, Liu M, et al. Hollow ZSM-5 with silicon-rich surface, double shells, and functionalized interior with metallic nanoparticles and carbon nanotubes [J]. Advanced Functional Materials, 2015, 25 (48): 7479-7487 [41] Zhou F, Gao Y, Ma H X, et al. Catalytic aromatization of methanol over post-treated ZSM-5 zeolites in the terms of pore structure and acid sites properties [J]. Molecular Catalysis, 2017, 438: 37-46 [42] Xu Y R, Lai W K, Dong Y Y, et al. Internal defects-oriented dissolution: controllable evolution of hollow ZSM-5 nano-structures [J]. CrystEngComm, 2018, 20 (37): 5625-5631 [43] Hong Z, Wang Z, Chen D, et al. Hollow ZSM-5 encapsulated Pt nanoparticles for selective catalytic reduction of NO by hydrogen [J]. Applied Surface Science, 2018, 440: 1037-1046 [44] Fu T J, Qi R Y, Wan W L, et al. fabrication of hollow mesoporous nanosized ZSM-5 catalyst with superior methanol-to-hydrocarbons performance by controllable desilication [J]. ChemCatChem, 2017, 9 (22): 4212-4224 [45] Abello S,Bonilla A,Perez-Ramirez J. Mesoporous ZSM-5 zeolite catalysts prepared by desilication with organic hydroxides and comparison with NaOH leaching [J]. Applied Catalysis A: General, 2009, 364 (1-2): 191-198 [46] Hidalgo C. Measurement of the acidity of various zeolites by temperature-programmed desorption of ammonia [J]. Journal of Catalysis, 1984, 85 (2): 362-369 [47] Ma Z, Fu T J, Wang Y J, et al. silicalite-1 derivational desilication-recrystallization to prepare Hollow nano-ZSM-5 and highly mesoporous micro-ZSM-5 catalyst for methanol to hydrocarbons [J]. Industrial & Engineering Chemistry Research, 2019, 58 (6): 2146-2158 [48] Verboekend D, Groen J C, Pérez-Ramírez J. Interplay of properties and functions upon introduction of mesoporosity in ITQ-4 zeolite [J]. Advanced Functional Materials, 2010, 20 (9): 1441-1450