六氟硅酸铵后处理对H-ZSM-5分子筛酸性影响的固体NMR研究

doi:10.11938/cjmr20212927

摘要/Abstract

摘要：

本文利用固体核磁共振（NMR）实验对六氟硅酸铵（AHFS）溶液洗涤前后H-ZSM-5分子筛上铝物种变化引起的酸性改变进行了研究.结果显示经AHFS洗涤处理后，分子筛上构成Brøsted酸的骨架四配位铝物种会部分减少；具有Lewis酸性的骨架三配位铝量在经AHFS脱铝处理后少量降低；同时AHFS温和脱铝的方式主要会引起分子筛上另一类具有Lewis酸性且含Al-OH的铝物种大量减少，从而导致处理后分子筛整体酸性的显著改变.

关键词: 六氟硅酸铵（AHFS）, 三甲基氧膦（TMPO）探针分子, 酸性, 固体核磁共振

Abstract:

In this study, solid-state nuclear magnetic resonance (NMR) spectroscopy was used to probe the changes of acidity of H-ZSM-5 zeolite caused by ammonium hexafluorosilicate (AHFS) washing-related changes of aluminium species. It was observed that the four-coordinate framework aluminum species with Brønsted acidity were partially reduced, while the tri-coordinated framework aluminum with Lewis acidity was slightly decreased after the AHFS treatment. However, AHFS washing was also found to induce mild dealumination and a significant reduction of aluminum species with Lewis acidity containing Al-OH group on zeolites, thus resulting in a remarkable change in the overall acidity of the zeolites.

Key words: ammonium hexafluorosilicate (AHFS), trimethylphosphine oxide (TMPO) probe molecules, acidity, solid-state nuclear magnetic resonance

中图分类号:

O482.53

王永祥,王强,徐君,夏清华,邓风. 六氟硅酸铵后处理对H-ZSM-5分子筛酸性影响的固体NMR研究[J]. 波谱学杂志, 2021, 38(4): 514-522.

Yong-xiang WANG,Qiang WANG,Jun XU,Qing-hua XIA,Feng DENG. The Effects of Ammonium Hexafluorosilicate Post-Treatment on the Acidity of H-ZSM-5 Zeolite Studied by Solid-State NMR Spectroscopy[J]. Chinese Journal of Magnetic Resonance, 2021, 38(4): 514-522.

图/表 7

图1

图2

表1

图3

图4

图5

图6

参考文献 34

1	TIAN P , WEI Y X , YE M , et al. Methanol to olefins (MTO): From fundamentals to commercialization[J]. ACS Catal, 2015, 5 (3): 1922- 1938. doi: 10.1021/acscatal.5b00007
2	ZHOU X , WANG C , CHU Y Y , et al. Observation of an oxonium ion intermediate in ethanol dehydration to ethene on zeolite[J]. Nat Commun, 2019, 10 (1): 1961. doi: 10.1038/s41467-019-09956-7
3	VOGT E T C , WECKHUYSEN B M . Fluid catalytic cracking: recent developments on the grand old lady of zeolite catalysis[J]. Chem Soc Rev, 2015, 44 (20): 7342- 7370. doi: 10.1039/C5CS00376H
4	MOLINER M , ROMáN-LESHKOV Y , DAVIS M E . Tin-containing zeolites are highly active catalysts for the isomerization of glucose in water[J]. Proc Nat Acad Sci U S A, 2010, 107 (14): 6164- 6168. doi: 10.1073/pnas.1002358107
5	HAAG W O , LAGO R M , WEISZ P B . The active site of acidic aluminosilicate catalysts[J]. Nature, 1984, 309 (5969): 589- 591. doi: 10.1038/309589a0
6	MAIER S M , JENTYS A , LERCHER J A . Steaming of zeolite BEA and its effect on acidity: A comparative NMR and IR spectroscopic study[J]. J Phys Chem C, 2011, 115 (16): 8005- 8013. doi: 10.1021/jp108338g
7	KAO H M , GREY C P , PITCHUMANI K , et al. Activation conditions play a key role in the activity of zeolite CaY: NMR and product studies of Brønsted acidity[J]. J Phys Chem A, 1998, 102 (28): 5627- 5638. doi: 10.1021/jp980385w
8	WANG Q L , GIANNETTO G , TORREALBA M , et al. Dealumination of zeolites Ⅱ. Kinetic study of the dealumination by hydrothermal treatment of a NH₄NaY zeolite[J]. J Catal, 1991, 130 (2): 459- 470. doi: 10.1016/0021-9517(91)90128-Q
9	YU Z W , LI S H , WANG Q , et al. Brønsted/Lewis acid synergy in H-ZSM-5 and H-MOR zeolites studied by ¹H and ²⁷Al DQ-MAS solid-state NMR spectroscopy[J]. J Phys Chem C, 2011, 115 (45): 22320- 22327. doi: 10.1021/jp203923z
10	YI X , LIU K , CHEN W , et al. Origin and structural characteristics of tri-coordinated extra-framework aluminum species in dealuminated zeolites[J]. J Am Chem Soc, 2018, 140 (34): 10764- 10774. doi: 10.1021/jacs.8b04819
11	GAO X Z , ZHANG Y , WANG X M , et al. Structure and acidity changes in ultra-stable y zeolites during hydrothermal aging: A solid-state NMR spectroscopy study[J]. Chinese J Magn Reson, 2020, 37 (1): 95- 103.
	高秀枝, 张翊, 王秀梅, 等. NMR研究超稳Y分子筛水热老化过程中结构与酸性的变化[J]. 波谱学杂志, 2020, 37 (1): 95- 103.
12	GAO W , QI G D , WANG Q , et al. Dual active sites on molybdenum/ZSM-5 catalyst for methane dehydroaromatization: insights from solid-state NMR spectroscopy[J]. Angew Chem Int Ed, 2021, 60 (19): 10709- 10715. doi: 10.1002/anie.202017074
13	GAO P , WANG Q , XU J , et al. Brønsted/Lewis acid synergy in methanol-to-aromatics conversion on Ga-modified ZSM-5 zeolites, As studied by solid-state NMR spectroscopy[J]. ACS Catal, 2018, 8 (1): 69- 74. doi: 10.1021/acscatal.7b03211
14	QI G D , WANG Q , XU J , et al. Synergic effect of active sites in zinc-modified ZSM-5 zeolites as revealed by high-field solid-state NMR spectroscopy[J]. Angew Chem Int Ed, 2016, 55 (51): 15826- 15830. doi: 10.1002/anie.201608322
15	CHEN X L , LV W , SU Q C , et al. Conversion of lignocellulose studied by nuclear magnetic resonance[J]. Chinese J Magn Reson, 2021, 38 (2): 277- 290.
	陈晓丽, 吕微, 苏秋成, 等. 核磁共振技术在生物质转化中的应用[J]. 波谱学杂志, 2021, 38 (2): 277- 290.
16	MORENO-RECIO M , SANTAMARíA-GONZáLEZ J , MAIRELES-TORRES P . Brönsted and Lewis acid ZSM-5 zeolites for the catalytic dehydration of glucose into 5-hydroxymethylfurfural[J]. Che Eng J, 2016, 303, 22- 30. doi: 10.1016/j.cej.2016.05.120
17	SUGANUMA S , HISAZUMI T , TARUYA K , et al. Influence of acidic property on catalytic activity and selectivity in dehydration of glycerol[J]. ChemistrySelect, 2017, 2 (20): 5524- 5531. doi: 10.1002/slct.201700941
18	WANG Z C , O'DELL L A , ZENG X , et al. Insight into three-coordinate aluminum species on ethanol-to-olefin conversion over ZSM-5 zeolites[J]. Angew Chem Int Ed, 2019, 58 (50): 18061- 18068. doi: 10.1002/anie.201910987
19	LI S H , ZHENG A M , SU Y C , et al. Brønsted/Lewis acid synergy in dealuminated HY zeolite: A combined solid-state NMR and theoretical calculation study[J]. J Am Chem Soc, 2007, 129 (36): 11161- 11171. doi: 10.1021/ja072767y
20	GROEN J C , BACH T , ZIESE U , et al. Creation of hollow zeolite architectures by controlled desilication of Al-Zoned ZSM-5 crystals[J]. J Am Chem Soc, 2005, 127 (31): 10792- 10793. doi: 10.1021/ja052592x
21	GARRALóN G , FORNéS V , CORMA A . Faujasites dealuminated with ammonium hexafluorosilicate: Variables affecting the method of preparation[J]. Zeolites, 1988, 8 (4): 268- 272. doi: 10.1016/S0144-2449(88)80122-2
22	KAO H M , CHEN Y C . ²⁷Al and ¹⁹F solid-state NMR studies of zeolite H-β dealuminated with ammonium hexafluorosilicate[J]. J Phys Chem B, 2003, 107 (15): 3367- 3375. doi: 10.1021/jp021680q
23	KAO H M , CHANG P C . Direct solid-state NMR spectroscopic evidence for the NH₄AlF₄ crystalline phase derived from zeolite HY dealuminated with ammonium hexafluorosilicate[J]. J Phys Chem B, 2006, 110 (39): 19104- 19107. doi: 10.1021/jp064938b
24	WANG Q L , TORREALBA M , GIANNETTO G , et al. Dealumination of Y zeolite with ammonium hexafluorosilicate: A SIMS-XPS study of the aluminum distribution[J]. Zeolites, 1990, 10 (7): 703- 706. doi: 10.1016/0144-2449(90)90084-5
25	SILVA J M , RIBEIRO M F , RAMôA RIBEIRO F , et al. Influence of the treatment of mordenite by ammonium hexafluorosilicate on physicochemical and catalytic properties[J]. Zeolites, 1996, 16 (4): 275- 280. doi: 10.1016/0144-2449(95)00138-7
26	SCHALLMOSER S , IKUNO T , WAGENHOFER M F , et al. Impact of the local environment of Brønsted acid sites in ZSM-5 on the catalytic activity in n-pentane cracking[J]. J Catal, 2014, 316, 93- 102. doi: 10.1016/j.jcat.2014.05.004
27	CHEN K Z , ABDOLRHAMANI M , SHEETS E , et al. Direct detection of multiple acidic proton sites in zeolite HZSM-5[J]. J Am Chem Soc, 2017, 139 (51): 18698- 18704. doi: 10.1021/jacs.7b10940
28	XIN S H , WANG Q , XU J , et al. The acidic nature of "NMR-invisible" tri-coordinated framework aluminum species in zeolites[J]. Chem Sci, 2019, 10 (43): 10159- 10169. doi: 10.1039/C9SC02634G
29	WANG Y X , XIN S H , CHU Y Y , et al. Influence of trimethylphosphine oxide loading on the measurement of zeolite acidity by solid-state NMR spectroscopy[J]. J Phys Chem C, 2021, 125 (17): 9497- 9506. doi: 10.1021/acs.jpcc.1c01789
30	ZHENG A M , ZHANG H L , LU X , et al. Theoretical predictions of ³¹P NMR chemical shift threshold of trimethylphosphine oxide absorbed on solid acid catalysts[J]. J Phys Chem B, 2008, 112 (15): 4496- 4505. doi: 10.1021/jp709739v
31	BRUS J , KOBERA L , SCHOEFBERGER W , et al. Structure of framework aluminum lewis sites and perturbed aluminum atoms in zeolites as determined by ²⁷Al{¹H} REDOR (3Q) MAS NMR spectroscopy and DFT/molecular mechanics[J]. Angew Chem Int Ed, 2015, 54 (2): 541- 545.
32	RAVI M , SUSHKEVICH V L , VAN BOKHOVEN J A . Towards a better understanding of Lewis acidic aluminium in zeolites[J]. Nat Mater, 2020, 19 (10): 1047- 1056. doi: 10.1038/s41563-020-0751-3
33	WIPER P V , AMELSE J , MAFRA L . Multinuclear solid-state NMR characterization of the Brønsted/Lewis acid properties in the BP HAMS-1B (H-[B]-ZSM-5) borosilicate molecular sieve using adsorbed TMPO and TBPO probe molecules[J]. J Catal, 2014, 316, 240- 250. doi: 10.1016/j.jcat.2014.05.017
34	ZHAO Q , CHEN W H , HUANG S J , et al. Discernment and quantification of internal and external acid sites on zeolites[J]. J Phys Chem B, 2002, 106 (17): 4462- 4469. doi: 10.1021/jp015574k

Position	δ_F₂^a	δ_F₁^a	δ_CS^b	P_Q/MHz^c
Al^IV-1	54.4	56.7	55.8	1.6
Al^IV-2	40.7	66.9	57.2	5.5
Al^VI	-0.8	0.9	0.3	1.4

[1]	陈翰迪,孔海宇,赵侦超,张维萍. 固体核磁共振结合密度泛函理论计算研究SSZ-39分子筛的钠离子落位与铝分布[J]. 波谱学杂志, 2021, 38(4): 543-551.
[2]	杨文杰,黄骏. 基于固体核磁共振技术的固体酸结构、酸性及活性分析[J]. 波谱学杂志, 2021, 38(4): 460-473.
[3]	夏锡锋,张文静,林芝晔,柯晓康,温玉洁,王芳,陈俊超,彭路明. 氧化物纳米材料表面结构与性质的固体核磁共振波谱研究[J]. 波谱学杂志, 2021, 38(4): 533-542.
[4]	王子春,黄骏,姜怡娇. 五配位铝强化硅铝固体酸的固体核磁共振研究[J]. 波谱学杂志, 2021, 38(4): 552-570.
[5]	史朝为,石攀,田长麟. 非天然氨基酸在蛋白质动态特性核磁共振研究中的应用[J]. 波谱学杂志, 2021, 38(4): 523-532.
[6]	肖瑶,夏长久,易先锋,刘凤庆,刘尚斌,郑安民. 固体核磁共振技术在锡硅分子筛表征中的应用[J]. 波谱学杂志, 2021, 38(4): 571-584.
[7]	高树树,徐舒涛,魏迎旭,刘中民. 固体核磁共振技术在甲醇制烯烃反应中的应用[J]. 波谱学杂志, 2021, 38(4): 433-447.
[8]	陈欣,付颖懿,岳斌,贺鹤勇. 固体核磁共振技术研究金属氧化物类固体酸催化剂的酸碱性[J]. 波谱学杂志, 2021, 38(4): 491-502.
[9]	张之杰, 李端秀, 罗春, 仇汝臣, 邓宗武, 张海禄. 晶体学辅助的2-吡啶甲酸固体¹³C化学位移理论计算归属[J]. 波谱学杂志, 2020, 37(1): 67-75.
[10]	雷振宇, 梁欣苗, 雷友义, 杨丽, 冯继文. 固体核磁共振技术在锂/钠离子电池碳负极中的应用及研究进展[J]. 波谱学杂志, 2020, 37(1): 28-39.
[11]	魏令, 张善民. 利用相位步进脉冲消除探头¹³C NMR背景信号[J]. 波谱学杂志, 2020, 37(1): 123-130.
[12]	高秀枝, 张翊, 王秀梅, 张智华, 徐广通. NMR研究超稳Y分子筛水热老化过程中结构与酸性的变化[J]. 波谱学杂志, 2020, 37(1): 95-103.
[13]	冯宗静, 杜亚平, 罗锋, 徐骏. 通过超宽¹³⁹La固体核磁共振波谱研究层状La(OH)₂NO₃[J]. 波谱学杂志, 2020, 37(1): 76-85.
[14]	王杨, 杨昌菊, 温玉洁, 陈俊超, 杜佳欢, 彭路明. 利用¹⁷O固体核磁共振波谱分析Ni/CeO₂表面镍离子含量[J]. 波谱学杂志, 2020, 37(1): 52-60.
[15]	梁力鑫, 邓风, 侯广进. 固体核磁共振魔角旋转条件下的定量交叉极化技术(英文)[J]. 波谱学杂志, 2020, 37(1): 1-15.