SAPO-34提升铁钒基催化剂抗碱性能研究

摘要/Abstract

摘要： 采用浸渍法制备Fe-VO_x/SAPO-34和Fe-VO_x/TiO₂脱硝催化剂,探究SAPO-34分子筛与TiO₂两种载体负载铁钒基氧化物催化活性及抗碱性能的差异。借助X射线衍射(XRD)、X射线光电子能谱(XPS)、氨气程序升温脱附(NH₃-TPD)、氢气程序升温还原(H₂-TPR)、原位红外漫反射(in-situ DRIFTs)等表征手段对催化剂的骨架结构、表面物化性质、氧化还原能力以及对反应气体的吸脱附情况进行分析。结果表明:SAPO-34分子筛内部特定的孔道结构和稳定的骨架,有利于活性组分在载体上均匀分散,降低碱金属对表面活性中心的物理覆盖作用;同时其表面丰富的酸位点能够作为碱金属捕获位,保护催化剂表面的活性中心,保证催化剂的吸附-反应过程能够正常进行,从而使Fe-VO_x/SAPO-34表现出良好的抗碱金属能力。

关键词: 碱金属, 铁钒化合物, 载体, 分子筛, 表面酸性, 低温活性

Abstract: Fe-VO_x/SAPO-34 and Fe-VO_x/TiO₂ catalysts were prepared by impregnation method to explore the catalytic activity and alkali metal resistance of SAPO-34 molecular sieve and TiO₂ supported iron vanadium-based oxides. The catalysts were characterized by means of XRD, XPS, NH₃-TPD, H₂-TPR and in-situ DRIFTs. The results show that: the specific pore structure and stable skeleton in SAPO-34 molecular sieve are conducive to the uniform dispersion of active components on the carrier and reduce the physical coverage of alkali metals on the surface active centers; at the same time, the rich acid sites can be used as alkali metal capture sites to protect the active center on the catalyst surface and ensure the normal adsorption reaction process of the catalyst, so that Fe-VO_x/SAPO-34 shows good alkali metal resistance.

Key words: alkali metal, iron vanadium compound, carrier, zeolite, surface acidity, low-temperature catalytic activity

中图分类号:

X701
TQ426

胡方方, 李顺, 蔡思翔, 姜宏, 马艳平. SAPO-34提升铁钒基催化剂抗碱性能研究[J]. 人工晶体学报, 2022, 51(3): 493-501.

HU Fangfang, LI Shun, CAI Sixiang, JIANG Hong, MA Yanping. Alkali Resistance of Iron Vanadium Based Oxides by SAPO-34[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2022, 51(3): 493-501.

参考文献

[1] 唐剑骁,马丽萍,王冬东,等.微波对Cu-ZSM-5催化剂结构及低温NH₃-SCR脱硝活性的影响[J].人工晶体学报,2017,46(8):1569-1574.
TANG J X, MA L P, WANG D D, et al. Influence of microwave on the structure and NH₃-SCR denitration activity of Cu-ZSM-5 catalysts[J]. Journal of Synthetic Crystals, 2017, 46(8): 1569-1574(in Chinese).
[2] YAO X J, KONG T T, YU S H, et al. Influence of different supports on the physicochemical properties and denitration performance of the supported Mn-based catalysts for NH₃-SCR at low temperature[J]. Applied Surface Science, 2017, 402: 208-217.
[3] KANG L, HAN L P, HE J B, et al. Improved NO_x reduction in the presence of SO₂ by using Fe₂O₃-promoted halloysite-supported CeO₂-WO₃ catalysts[J]. Environmental Science & Technology, 2019, 53(2): 938-945.
[4] MARBERGER A, ELSENER M, FERRI D, et al. Generation of NH₃ selective catalytic reduction active catalysts from decomposition of supported FeVO₄[J]. ACS Catalysis, 2015, 5(7): 4180-4188.
[5] CHEN L, LI J H, GE M F. The poisoning effect of alkali metals doping over nano V₂O₅-WO₃/TiO₂ catalysts on selective catalytic reduction of NO_x by NH₃[J]. Chemical Engineering Journal, 2011, 170(2/3): 531-537.
[6] WANG C, YAN W J, WANG Z X, et al. The role of alkali metal ions on hydrothermal stability of Cu/SSZ-13 NH₃-SCR catalysts[J]. Catalysis Today, 2020, 355: 482-492.
[7] 仲兆平,张茜芸,杨碧源,等.V₂O₅/TiO₂烟气脱硝催化剂的钾、钠、锌、磷中毒及再生[J].东南大学学报(自然科学版),2013,43(3):548-552.
ZHONG Z P, ZHANG X Y, YANG B Y, et al. Effects of potassium, sodium, zinc and phosphorus on flue gas de-NO_x performance over V₂O₅/TiO₂ catalysts[J]. Journal of Southeast University (Natural Science Edition), 2013, 43(3): 548-552(in Chinese).
[8] 高凤雨,唐晓龙,易红宏,等.商用SCR催化剂的钠中毒及再生[J].中南大学学报(自然科学版),2015,46(6):2382-2390.
GAO F Y, TANG X L, YI H H, et al. Sodium poisoning mechanism and regeneration of commercial de-NO_x SCR catalysts[J]. Journal of Central South University (Science and Technology), 2015, 46(6): 2382-2390(in Chinese).
[9] GAO F Y, TANG X L, YI H H, et al. The poisoning and regeneration effect of alkali metals deposed over commercial V₂O₅-WO₃/TiO₂ catalysts on SCR of NO by NH₃[J]. Chinese Science Bulletin, 2014, 59(31): 3966-3972.
[10] 徐托雨,蔡思翔.硫酸化改性对TiO₂负载的铈基脱硝催化剂的活性及抗碱金属性能的影响[J].北京化工大学学报(自然科学版),2021,48(1):25-33.
XU T Y, CAI S X. Effect of sulfation on the activity and alkali resistance of TiO₂-supported cerium-based deNO_x catalysts[J]. Journal of Beijing University of Chemical Technology (Natural Science Edition), 2021, 48(1): 25-33(in Chinese).
[11] PENG Y, LIU C X, ZHANG X Y, et al. The effect of SiO₂ on a novel CeO₂-WO₃/TiO₂ catalyst for the selective catalytic reduction of NO with NH₃[J]. Applied Catalysis B: Environmental, 2013, 140/141: 276-282.
[12] HUANG Z W, GU X, WEN W, et al. A “smart” hollandite DeNO_x catalyst: self-protection against alkali poisoning[J]. Angewandte Chemie, 2013, 52(2): 660-664.
[13] CHANG H Z, MA L, YANG S J, et al. Comparison of preparation methods for ceria catalyst and the effect of surface and bulk sulfates on its activity toward NH₃-SCR[J]. Journal of Hazardous Materials, 2013, 262: 782-788.
[14] YU Y K, CHEN C W, MA M D, et al. SO₂ promoted in situ recovery of thermally deactivated Fe₂(SO₄)₃/TiO₂ NH₃-SCR catalysts: from experimental work to theoretical study[J]. Chemical Engineering Journal, 2019, 361: 820-829.
[15] ZHAO W R, TANG Y, WAN Y P, et al. Promotion effects of SiO₂ or/and Al₂O₃ doped CeO₂/TiO₂ catalysts for selective catalytic reduction of NO by NH₃[J]. Journal of Hazardous Materials, 2014, 278: 350-359.
[16] MU J C, LI X Y, SUN W B, et al. Inductive effect boosting catalytic performance of advanced Fe_1-xV_xO_δ catalysts in low-temperature NH₃ selective catalytic reduction: insight into the structure, interaction, and mechanisms[J]. ACS Catalysis, 2018, 8(8): 6760-6774.
[17] WATANABE S, MA X L, SONG C S. Characterization of structural and surface properties of nanocrystalline TiO₂-O₂ mixed oxides by XRD, XPS, TPR, and TPD[J]. The Journal of Physical Chemistry C, 2009, 113(32): 14249-14257.
[18] YAN T, LIU Q, WANG S H, et al. Promoter rather than inhibitor: phosphorus incorporation accelerates the activity of V₂O₅-WO₃/TiO₂ catalyst for selective catalytic reduction of NO_x by NH₃[J]. ACS Catalysis, 2020, 10(4): 2747-2753.
[19] CHEN X B, WANG P L, FANG P, et al. Design strategies for SCR catalysts with improved N₂ selectivity: the significance of nano-confining effects by titanate nanotubes[J]. Environmental Science: Nano, 2017, 4(2): 437-447.
[20] CHEN J H, WANG B, YUAN K, et al. One-pot in situ synthesis of Cu-SAPO-34/SiC catalytic membrane with enhanced binding strength and chemical resistance for combined removal of NO and dust[J]. Chemical Engineering Journal, 2021, 420: 130425.
[21] ALSULAMI Q A, RAJEH A, MANNAA M A, et al. Preparation of highly efficient sunlight driven photodegradation of some organic pollutants and H₂ evolution over rGO/FeVO₄ nanocomposites[J]. International Journal of Hydrogen Energy, 2021, 46(54): 27349-27363.
[22] WU G X, FENG X, ZHANG H L, et al. The promotional role of Ni in FeVO₄/TiO₂ monolith catalyst for selective catalytic reduction of NO_x with NH₃[J]. Applied Surface Science, 2018, 427: 24-36.
[23] 曹荣,赵洪,程谟杰,等.HZSM-5与ZnO/SiO₂的固相反应[J].燃料化学学报,1995,23(4):362-368.
CAO R, ZHAO H, CHENG M J, et al. Solid state reaction of HZSM-5 and ZnO/SiO₂[J]. Journal of Fuel Chemistry and Technology, 1995, 23(4): 362-368(in Chinese).
[24] CASANOVA M, NODARI L, SAGAR A, et al. Preparation, characterization and NH₃-SCR activity of FeVO₄ supported on TiO₂-WO₃-SiO₂[J]. Applied Catalysis B: Environmental, 2015, 176/177: 699-708.
[25] LIU J, MEEPRASERT J, NAMUANGRUK S, et al. Facet-activity relationship of TiO₂ in Fe₂O₃/TiO₂ nanocatalysts for selective catalytic reduction of NO with NH₃: in situ DRIFTs and DFT studies[J]. The Journal of Physical Chemistry C, 2017, 121(9): 4970-4979.
[26] WANG D, PENG Y, XIONG S C, et al. De-reducibility mechanism of titanium on maghemite catalysts for the SCR reaction: an in situ DRIFTS and quantitative kinetics study[J]. Applied Catalysis B: Environmental, 2018, 221: 556-564.
[27] LIU F D, SHAN W P, LIAN Z H, et al. The smart surface modification of Fe₂O₃ by WO_x for significantly promoting the selective catalytic reduction of NO_x with NH₃[J]. Applied Catalysis B: Environmental, 2018, 230: 165-176.
[28] MA L, CHENG Y S, CAVATAIO G, et al. In situ DRIFTS and temperature-programmed technology study on NH₃-SCR of NO_x over Cu-SSZ-13 and Cu-SAPO-34 catalysts[J]. Applied Catalysis B: Environmental, 2014, 156/157: 428-437.