DFT计算结合固体NMR研究富铝SSZ-13的铝分布和Brønsted酸性

doi:10.3866/PKU.WHXB201903021

摘要/Abstract

摘要： 具有菱沸石（CHA）结构的SSZ-13分子筛在甲醇制烯烃（MTO）及柴油机车尾气氨选择性催化还原（NH₃-SCR）反应中具有重要的应用，采用富铝SSZ-13可以调节MTO反应的烯烃选择性和提升NH₃-SCR的低温脱硝活性，因此SSZ-13中的铝含量和分布与对应的酸性决定了其催化性能。本文采用密度泛函理论结合固体核磁共振实验研究了富铝和富硅H-SSZ-13的Al位置与Brønsted酸强度的内在关系。通过计算取代能发现，对于孤立Al位，质子位于Al周围4个不同O位时能量差异较小，最稳定的B酸位点是O（1）-H。对于富铝SSZ-13，两个Al原子位于同一六元环的对位是Al-Si-Si-Al（NNNN）序列中最稳定的结构，而Al-Si-Al（NNN）序列中能量最优的Al分布是两个铝原子排布于六棱柱上下不同的六元环上。通过计算最稳定构型下的质子亲和势、NH₃脱附能和吸附氘代乙腈后的¹H NMR化学位移，发现富铝SSZ-13中含有Si（2Al）分布的NNN序列导致了其Brønsted酸强度弱于高硅的分子筛。分峰拟合²⁹Si魔角旋转核磁共振（MAS NMR）谱图表明富铝SSZ-13中Si（2Al）的含量在43%以上，而吸附氘代乙腈后的¹H MAS NMR实验显示富铝SSZ-13的桥羟基化学位移向低场移动，进一步证明富铝SSZ-13具有较弱的Brønsted酸强度。

关键词: 密度泛函理论, 固体核磁共振, SSZ-13分子筛, Al分布, Brønsted酸性

Abstract: SSZ-13 zeolite with a chabazite (CHA) topology structure has important applications for methanol to olefin (MTO) conversion and selective catalytic reduction of nitrogen oxides (NO_x) by ammonia (NH₃-SCR) to reduce diesel engine exhaust emissions. It has been reported that the Al-rich SSZ-13 zeolite can be used to tune the selectivity of olefins in the MTO reaction, and significantly enhance NO conversions at lower temperatures in NH₃-SCR. Thus, the aluminum content and distribution as well as the corresponding acidity in SSZ-13 zeolite determine the catalytic performance of the zeolite for different catalytic reactions. Herein, quantum chemical computing using density functional theory (DFT) combined with multinuclear solid-state nuclear-magnetic-resonance (NMR) experiments were performed to investigate the correlation of Al location and Brønsted acidity of H-SSZ-13 zeolite with the Si/Al ratio varying from 5.8 to 25. The most favorable acid site in the 1Al model is O(1)-H in which a proton is bonded with the O(1) atom near the isolated Al atom of the zeolite framework. Nevertheless, energy differences were rather small when comparing the substitution energies of an Al atom replacing a Si atom in the zeolite framework with a proton located in different O sites. As the Si/Al ratio decreased, the Al-rich SSZ-13 zeolite contained more Al substitutions in its framework. This system exhibited the lowest substitution energy when two Al atoms were located at the diagonal of the same six-membered ring for the Al-Si-Si-Al (NNNN) sequence in the framework of the Al-rich SSZ-13 zeolite. However, for the Al-Si-Al (NNN) sequence, the most favorable distribution involved two Al atoms located in different six-membered rings of the double six-membered ring units (D6R). The proton affinities (PA), NH₃ desorption energies, and ¹H NMR chemical shifts after d3-acetonitrile adsorption were calculated in the most stable models to characterize the Brønsted acid strength of the SSZ-13 zeolite with different Si/Al ratios. All computing results suggested that the Al-rich SSZ-13 zeolite exhibited weaker Brønsted acid strength than that of the Si-rich counterpart due to the presence of Si(2Al) groupings with the NNN sequence in the framework. Quantitative ²⁹Si magic-angle spinning (MAS) NMR measurements after deconvolution demonstrated that the content of Si(2Al) groupings in the Al-rich SSZ-13 was > 43%. The ¹H MAS NMR experiments after d3-acetonitrile adsorption showed that the chemical shift of the bridging hydroxyls in the Al-rich SSZ-13 moved to the lower field, further confirming that it had a weaker Brønsted acid strength than the Si-rich counterpart.

Key words: DFT, Solid-state NMR, SSZ-13 zeolite, Al distribution, Brø nsted acidity

MSC2000:

O641

李诗涵, 赵侦超, 李世坤, 邢友东, 张维萍. DFT计算结合固体NMR研究富铝SSZ-13的铝分布和Brønsted酸性[J]. 物理化学学报, 1903021.

LI Shihan, ZHAO Zhenchao, LI Shikun, XING Youdong, ZHANG Weiping. Aluminum Distribution and Brønsted Acidity of Al-Rich SSZ-13 Zeolite: A Combined DFT Calculation and Solid-State NMR Study[J]. Acta Physico-Chimica Sinica, 1903021.

参考文献

(1) Yang, B.; Guo, C.; Cheng, J. Chem. Eng. Prog. 2014, 33, 368.[杨博, 郭翠梨, 程景耀. 化工进展, 2014, 33, 368.]doi: 10.3969/j.issn.1000-6613.2014.02.018
(2) Zhang, R.; Liu, N.; Lei, Z.; Chen, B. Chem. Rev. 2016, 116, 3658. doi: 10.1021/acs.chemrev.5b00474
(3) Zhou, Z.; Wang, Z.; Liu, Z. Sci. China Chem. 2018, 48, 562.[周子正, 王智华, 刘志明. 中国科学: 化学, 2018, 48, 562.]doi: 10.1360/N032017-00215
(4) Bull, I.; Boorse, R. S.; Jaglowski, W. M.; Koermer, G. S.; Moini, A.; Patchett, J. A.; Xue, W.; Burk, P.; Dettling, J. C.; Caudle, M. T.Processes for Reducing Nitrogen Oxides Using Copper Cha Zeolite Catalysts. U.S. Patent 8404203.B2, 3013-03-26
(5) Beale, A. M.; Gao, F.; Lezcano-Gonzalez, I.; Peden, C. H. F.; Szanyi, J. Chem. Soc. Rev. 2015, 44, 7371. doi: 10.1039/c5cs00108k
(6) Song, J.; Wang, Y.; Walter, E. D.; Washton, N. M.; Mei, D.; Kovarik, L.; Engelhard, M. H.; Prodinger, S.; Wang, Y.; Peden, C. H. F.; et al. ACS Catal. 2017, 7, 8214. doi: 10.1021/acscatal.7b03020
(7) Yu, H.; Zhang, G.; Han, L.; Chang, L.; Bao, W.; Wang, J. Acta Phys. -Chim. Sin. 2015, 31, 2165. [俞华峰, 张国佩, 韩丽娜, 常丽萍, 鲍卫仁, 王建成. 物理化学学报, 2015, 31, 2165.]doi: 10.3866/PKU.WHXB201509184
(8) Zhao, Z.; Yu, R.; Zhao, R.; Shi, C.; Gies, H.; Xiao, F.; De Vos, D.; Yokoi, T.; Bao, X.; Kolb, U.; et al. Appl. Catal. B: Environ. 2017, 217, 421. doi: 10.1016/j.apcatb.2017.06.013
(9) Gao, F.; Wang, Y.; Washton, N. M.; Kollar, M.; Szanyi, J.; Peden, C.H. F. J. Catal. 2015, 331, 25. doi: 10.1016/j.jcat.2015.08.004
(10) Deimund, M. A.; Harrison, L.; Lunn, J. D.; Liu, Y.; Malek, A.; Shayib, R.; Davis, M. E. ACS Catal. 2016, 6, 542. doi: 10.1021/acscatal.5b01450
(11) Di Iorio, J. R.; Nimlos, C. T.; Gounder, R. ACS Catal. 2017, 7, 6663. doi: 10.1021/acscatal.7b01273
(12) Zhao, Z.; Xing, Y.; Li, S.; Meng, X.; Xiao, F.; McGuire, R.; Parvulescu, A. N.; Müller, U.; Zhang, W. J. Phys. Chem. C 2018, 122, 9973. doi: 10.1021/acs.jpcc.8b01423
(13) Civalleri, B.; Ferrari, A. M.; Llunell, M.; Orlando, R.; Mérawa, M.; Ugliengo, P. Chem. Mater. 2003, 15, 3996. doi: 10.1021/cm0342804
(14) Zheng, A.; Chen, L.; Yang, J.; Zhang, M.; Su, Y.; Yue, Y.; Ye, C.; Deng, F. J. Phys. Chem. B 2005, 109, 24273. doi: 10.1021/jp0527249
(15) Zheng, A.; Liu, S. B.; Deng, F. Chem. Rev. 2017, 117, 12475. doi: 10.1021/acs.chemrev.7b00289
(16) Li, S.; Li, J.; Zheng, A.; Deng, F. Acta Phys. -Chim. Sin. 2017, 33, 270. [李申慧, 李静, 郑安民, 邓风. 物理化学学报, 2017, 33, 270.]doi: 10.3866/PKU.WHXB201611022
(17) Sazama, P.; Tabor, E.; Klein, P.; Wichterlova, B.; Sklenak, S.; Mokrzycki, L.; Pashkkova, V.; Ogura, M.; Dedecek, J. J. Catal. 2016, 333, 102. doi: 10.1016/j.jcat.2015.10.010
(18) Zhang, W.; Xu, S.; Han, X.; Bao, X. Chem. Soc. Rev. 2012, 41 (1), 192. doi: 10.1039/c1cs15009j
(19) Shah, R.; Gale, J. D.; Payne, M. C. J. Phys. Chem-Us 1996, 100, 11688. doi: 10.1021/Jp960365z
(20) Lo, C.; Trout, B. L. J. Catal. 2004, 227 (1), 77. doi: 10.1016/j.jcat.2004.06.018
(21) Solans-Monfort, X.; Sodupe, M.; Branchadell, V.; Sauer, J.; Orlando, R.; Ugliengo, P. J. Phys. Chem. B 2005, 109, 3539. doi: 10.1021/jp045531e
(22) Haw, J. F.; Hall, M. B.; Alvarado-Swaisgood, A. E.; Munson, E. J.; Lin, Z.; Beck, L. W.; Howard, T. J. Am. Chem. Soc. 1994, 116, 7308. doi: 10.1021/ja00095a039
(23) Gil, B.; Zones, S. I.; Hwang, S. J.; Bejblová, M.; Čejka, J. J. Phys. Chem. C 2008, 112, 2997. doi: 10.1021/jp077687v
(24) Calligaris, M.; Nardin, G.; Randaccio, L. Zeolites 1983, 3, 205. doi: 10.1016/0144-2449(83)90008-8
(25) Zheng, A.; Zhang, H.; Chen, L.; Yue, Y.; Ye, C.; Deng, F. J. Phys. Chem. B 2007, 111, 3085. doi: 10.1021/jp067340c
(26) Dunning, T. H. J. Phys. Chem. A 2000, 104, 9062. doi: 10.1021/jp001507z
(27) Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Scuseria, G. E.; Robb, M. A.; Cheeseman, J.R.; Scalmani, G.; Barone, V.; Mennucci, B.; Petersson, G. A.; et al. Gaussian 09, Revision D.01; Gaussian Inc:
Wallingford, CT, 2013(28) Jobic, H.; Tuel, A.; Krossner, M.; Sauer, J. J. Phys. Chem. C 1996, 100, 19545. doi: 10.1021/jp9619954
(29) Zygmunt, S. A.; Curtiss, L. A.; Iton, L. E.; Erhardt, M. K. J. Phys. Chem-Us 1996, 100, 6663. doi: 10.1021/Jp952913z
(30) Ryder, J. A.; Chakraborty, A. K.; Bell, A. T. J. Phys. Chem. B 2000, 104, 6998. doi: 10.1021/jp9943427
(31) Wang, J.; Li, S.; Zhao, Z.; Zhou, D.; Lu, A.; Zhang, W. Acta Phys. -Chim. Sin. 2016, 32, 1666. [王娟, 李世坤, 赵侦超, 周丹红, 陆安慧, 张维萍. 物理化学学报, 2016, 32, 1666.]doi: 10.3866/PKU.WHXB201604012
(32) Li, S.; Zhao, Z.; Zhao, R.; Zhou, D.; Zhang, W. ChemCatChem 2017, 9, 1494. doi: 10.1002/cctc.201601623
(33) Zhao, R.; Zhao, Z.; Li, S.; Zhang, W. J. Phys. Chem. Lett. 2017, 8, 2323. doi: 10.1021/acs.jpclett.7b00711
(34) Calligaris, M.; Nardin, G.; Randaccio, L.; Chiaramonti, P. C. Acta. Crystallogr. B 1982, 38, 602. doi: Doi 10.1107/S0567740882003483
(35) Jeanvoine, Y.; Angyan, J. G.; Kresse, G.; Hafner, J. J. Phys. Chem. B 1998, 102, 5573. doi: 10.1021/Jp980341n
(36) Nielsen, M.; Brogaard, R. Y.; Falsig, H.; Beato, P.; Swang, O.; Svelle, S. ACS Catal. 2015, 5, 7131. doi: 10.1021/acscatal.5b01496
(37) Smith, L. J.; Davidson, A.; Cheetham, A. K. Catal. Lett. 1997, 49, 143. doi: 10.1023/A:1019097019846
(38) Wang, N.; Zhang, M.; Yu, Y. Micropor. Mesopor. Mat. 2013, 169, 47. doi: 10.1016/j.micromeso.2012.10.019
(39) Chai, J. D.; Head-Gordon, M. Phys. Chem. Chem. Phys. 2008, 10, 6615. doi: 10.1039/b810189b
(40) Jänchen, J.; Van Wolput, J. H. M. C.; Van de Ven, L. J. M.; De Haan, J. W.; Van Santen, R. A. Catal. Lett. 1996, 39, 147. doi: 10.1007/bf00805574
(41) Dai, W.; Sun, X.; Tang, B.; Wu, G.; Li, L.; Guan, N.; Hunger, M. J. Catal. 2014, 314, 10. doi: 10.1016/j.jcat.2014.03.006

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