Selective catalytic reduction of nitric oxide with propylene in excess oxygen over Fe-Mn/Beta catalysts
-
摘要: 以Beta分子筛为载体,采用等体积浸渍法制备Fe-Mn/Beta催化剂,并对其在富氧条件下丙烯选择性催化还原NO性能进行了研究。通过N2吸附-脱附、X射线衍射(XRD)、X射线光电子能谱(XPS)、透射电子显微镜(TEM)、程序升温还原(H2-TPR)和原位漫反射傅里叶变换红外光谱(in-situ DRIFTS)等研究手段对催化剂进行表征,考察Mn组分对催化剂的物理化学性质、C3H6-SCR反应活性和反应中间产物的影响。结果表明,引入Mn物种可以显著提高Fe-Mn/Beta催化剂的低温催化活性,1.5Fe1.0Mn/Beta催化剂NO还原效率350℃最高可达99.4%,在250-400℃反应温度下显示出很高的反应活性和N2选择性。原位红外光谱研究表明,分子筛离子交换位上孤立的铁离子是丙烯选择性氧化的主要活性位,分散良好的MnO2物种不能提高催化剂对丙烯的活化能力,但有助于促进形成NO2吸附物种,从而提升了Fe-Mn/Beta催化剂的低温C3H6-SCR性能。经高温水热老化处理后,Fe-Mn/Beta催化剂脱硝活性明显下降,这与孤立的Fe3+离子迁移形成FexOy团聚物种有关。Abstract: Fe-Mn/Beta catalysts were prepared by incipient wet-impregnation methods and used for selective catalytic reduction of nitric oxide with propylene in excess oxygen. The catalysts were characterized using N2-physisorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), H2-temperature programmed reduction (H2-TPR) and in-situ diffuse reflectance infrared Fouier transform spectroscopy (in-situ DRIFTS) techniques. The effects of Mn component on the physicochemical properties, C3H6-SCR activity and reaction intermediates of catalysts were also investigated. The results showed that C3H6-SCR activity of Fe-Mn/Beta catalysts at low temperature could be significantly improved by introducing Mn species. 1.5Fe1.0Mn/Beta catalyst achieved the highest activity with a nitrogen oxide conversion of 99.4% at 350℃, which possessed high catalytic performance and N2 selectivity within the temperature window of 250-400℃. Based on the in-situ DRIFT studies, the isolated Fe3+ ions at the ion-exchange sites were the main active sites for selective oxidation of propylene. Although the well-dispersed MnO2 species could not improve the activation ability of the catalysts for propylene, they would enhance the formation of NO2 adsorption species, then promoted C3H6-SCR activity at the low temperature. The significant decrease of SCR activity after hydrothermal aging of Fe-Mn/Beta catalysts might be due to the migration of isolated Fe3+ ions into oligomeric clusters.
-
Key words:
- selective catalytic reduction /
- NO /
- C3H6 /
- manganese /
- hydrothermal aging
-
图 2 Fe-Mn/Beta催化剂上C3H6-SCR反应NO转化率(a)、N2选择性(b)和C3H6转化率(c)
Figure 2 NO conversion (a), N2 selectivity (b) and C3H6 conversion (c) over Fe-Mn/Beta catalysts
reaction conditions: 0.05%NO, 0.05%C3H6, 5%O2 and balance N2, GHSV=15000 mL/(g·h)
—□—: 1.5Fe/Beta; —○—: 1.5Mn/Beta; —◆—: 1.5Fe0.5Mn/Beta; —●—: 1.5Fe1.0Mn/Beta; —■—: 1.5Fe1.5Mn/Beta图 9 高温老化、高温水热老化对1.5Fe1.0Mn/Beta催化剂上C3H6-SCR反应活性的影响
Figure 9 NO conversion over the fresh and aged 1.5Fe1.0Mn/Beta catalysts the hydrothermal aging was performed at 700 ℃ for 24 h in the presence of 10% H2O and 20% O2 or 20% O2
reaction conditions: 0.05%NO, 0.05% C3H6, 5%O2, and GHSV=15000 mL/(g·h)
—○—: 1.5Fe1.0Mn/Beta-fresh; —●—: 1.5Fe1.0Mn/Beta-aged; —◆—: 1.5Fe1.0Mn/Beta-aged (10% H2O)表 1 Fe-Mn/Beta催化剂样品的孔结构特性
Table 1 Properties of H-Beta and Fe-Mn/Beta catalyst samples
Sample Specific surface area A/(m2·g-1) Pore volume v/(mL·g-1) Pore diameter d/nm 1.5Fe/Beta 512.1 0.541 4.2 1.5Fe1.0Mn/Beta 506.7 0.517 4.1 1.5Mn/Beta 431.6 0.450 4.2 H-Beta 519.9 0.517 4.0 -
[1] GRANGER P, PARVULESCU V I. Catalytic NOx abatement systems for mobile sources:From three-way to lean burn after-treatment technologies[J]. Chem Rev, 2011, 111(5):3155-3207. http://cn.bing.com/academic/profile?id=e83b0eb6b5f39da71e8f42c0405ba069&encoded=0&v=paper_preview&mkt=zh-cn [2] HAILONG L I, XIAO P, WANG T, ZHU J J, JINLIN L I. Recent progress on catalysts used for NO decomposition[J]. Sci Sin:Chim, 2014, 44(12):1951-1965. http://cn.bing.com/academic/profile?id=c8fab16f2f00e547e26501e7dd0140d1&encoded=0&v=paper_preview&mkt=zh-cn [3] 贺泓, 刘福东, 余运波, 单文坡.环境友好的选择性催化还原氮氧化物催化剂[J].中国科学化学, 2012, 42(4):446-468. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=zgkx-cb201204008HE Hong, LIU Fu-dong, YU Yun-bo, SHAN Wen-po. Environmental-friendly catalysts for the selective catalytic reduction of NOx[J]. Sci Sin:Chim, 2012, 42(4):446-468. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=zgkx-cb201204008 [4] ZHOU H, SU Y, LIAO W, DENG W, ZHONG F. NO reduction by propane over monolithic cordierite-based Fe/Al2O3 catalyst:Reaction mechanism and effect of H2O/SO2[J]. Fuel, 2016, 182:352-360. [5] 董士林, 苏亚欣, 刘欣, 李前程, 袁旻昊, 周皞, 邓文义. Fe/Ti-PILC用于C3H6选择性催化还原NO的研究[J].燃料化学学报, 2018, 46(10):1231-1239. doi: 10.3969/j.issn.0253-2409.2018.10.011DONG Shi-lin, SU Ya-xin, LIU Xin, LI Qian-cheng, YUAN Min-hao, ZHOU Hao, DENG Wen-yi. Experimental study on selective catalytic reduction of NO by C3H6 over Fe/Ti-PILC catalysts[J]. J Fuel Chem Technol, 2018, 46(10):1231-1239. doi: 10.3969/j.issn.0253-2409.2018.10.011 [6] 周皞, 苏亚欣, 邓文义, 钟方川.负载金属分子筛类催化剂上HC-SCR研究进展[J].环境科学与技术, 2015, 38(10):64-73. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=hjkxyjs201510013ZHOU Hao, SU Ya-xin, DENG Wen-yi, ZHONG fang-chuan. A review of HC-SCR over metal-based zeolite catalysts[J]. Environ Sci Technol, 2015, 38(10):64-73. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=hjkxyjs201510013 [7] GRANGER P, PARVULESCU V I. Catalytic NOx abatement systems for mobile sources:From three-way to lean burn after-treatment technologies[J]. Chem Rev, 2011, 111(5):3155-3207. http://cn.bing.com/academic/profile?id=e83b0eb6b5f39da71e8f42c0405ba069&encoded=0&v=paper_preview&mkt=zh-cn [8] ROSAS J M, RUIZ-ROSAS R, RODRÍGUEZ-MIRASOL J, CORDERO T. A kinetic study for NO catalytic reduction on silica sub-micron diameter tubes with platinum nanoparticles[J]. Chem Eng J, 2017, 327:343-350. http://cn.bing.com/academic/profile?id=da62e86113c52c4b11867d077791d502&encoded=0&v=paper_preview&mkt=zh-cn [9] ZHOU H, GE M, WU S, YE B, SU Y. Iron based monolithic catalysts supported on Al2O3, SiO2, and TiO2:A comparison for NO reduction with propane[J]. Fuel, 2018, 220:330-338. http://cn.bing.com/academic/profile?id=f31d38a26be193200419b117dca6ddbe&encoded=0&v=paper_preview&mkt=zh-cn [10] 杨溪, 苏亚欣, 钱文燕, 袁旻昊, 周皞, 邓文义, 赵兵涛. Fe-Ag/Al2O3催化丙烯还原NO的实验研究[J].燃料化学学报, 2017, 45(11):1365-1375 doi: 10.3969/j.issn.0253-2409.2017.11.012YANG Xi, SU Ya-xin, QIAN Wen-yan, YUAN Min-hao, ZHOU Hao, DENG Wen-yi, ZHAO Bing-tao. Experimental study on selective catalytic reduction of NO by C3H6 over Fe-Ag/Al2O3 catalysts[J]. J Fuel Chem Technol, 2017, 45(11):1365-1375. doi: 10.3969/j.issn.0253-2409.2017.11.012 [11] LI L, GUAN N. HC-SCR reaction pathways on ion exchanged ZSM-5 catalysts[J]. Microporous Mesoporous Mater, 2009, 117(1):450-457. http://cn.bing.com/academic/profile?id=e18a524855d1e95c7c3fa283e97d7f68&encoded=0&v=paper_preview&mkt=zh-cn [12] YASHNIK S A, SALNIKOV A V, VASENIN N T, ANUFRIENKO V F, ISMAGILOV Z R. Regulation of the copper-oxide cluster structure and DeNOx activity of Cu-ZSM-5 catalysts by variation of OH/Cu2+[J]. Catal Today, 2012, 197(1):214-227. [13] 刘福东, 单文坡, 石晓燕, 张长斌, 贺泓.用于NH3选择性催化还原NO的非钒基催化剂研究进展[J].催化学报, 2011, 32(7):1113-1128. http://d.old.wanfangdata.com.cn/Periodical/cuihuaxb201107002LIU Fu-dong, SHAN Wen-po, SHI Xiao-yan, ZHANG Chang-bin, HE Hong. Research progress in vanadium-Free catalysts for the selective catalytic reduction of NO with NH3[J]. Chin J Catal, 2011, 32(7):1113-1128. http://d.old.wanfangdata.com.cn/Periodical/cuihuaxb201107002 [14] WANG J, ZHAO H, HALLER G, LI Y. Recent advances in the selective catalytic reduction of NOx with NH3 on Cu-Chabazite catalysts[J]. Appl Catal B:Environ, 2017, 202:346-354. doi: 10.1016/j.apcatb.2016.09.024 [15] METKAR P S, SALAZAR N, MUNCRIEF R, BALAKOTAIAH V, HAROLD M P. Selective catalytic reduction of NO with NH3 on iron zeolite monolithic catalysts:Steady-state and transient kinetics[J]. Appl Catal B:Environ, 2011, 104(1/2):110-126. https://www.sciencedirect.com/science/article/pii/S0926337311000920 [16] CHEN H Y, SACHTLER W M H. Activity and durability of Fe/ZSM-5 catalysts for lean burn NOx reduction in the presence of water vapor[J]. Catal Today, 1998, 42(1):73-83. https://www.onacademic.com/detail/journal_1000034607354410_9eb2.html [17] YANG T T, BI H T, CHENG X. Effects of O2, CO2 and H2O on NOx adsorption and selective catalytic reduction over Fe/ZSM-5[J]. Appl Catal B:Environ, 2011, 102(1/2):163-171. https://www.sciencedirect.com/science/article/pii/S0926337310005266 [18] PAN H, GUO Y, BI H T. NOx adsorption and reduction with C3H6 over Fe/zeolite catalysts:Effect of catalyst support[J]. Chem Eng J, 2015, 280:66-73. https://www.sciencedirect.com/science/article/pii/S1385894715007810 [19] HE C, WANG Y, CHENG Y, LAMBERT C K, YANG R T. Activity, stability and hydrocarbon deactivation of Fe/Beta catalyst for SCR of NO with ammonia[J]. Appl Catal A:Gen, 2009, 368(1):121-126. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=3c0048be5b183e9e60e3db6390e64b95 [20] 孔志坚, 王成, 丁正南, 陈银飞, 张泽凯. Li改性MnO2及LiMn2O4催化NH3-SCR反应性能研究[J].燃料化学学报, 2014, 42(12):1447-1454. doi: 10.3969/j.issn.0253-2409.2014.12.006KONG Zhi-jian, WANG Cheng, DING Zheng-nan, CHEN Yin-fei, ZHANG Ze-kai. Li-modified MnO2 catalyst and LiMn2O4 for selective catalytic reduction of NO with NH3[J]. J Fuel Chem Technol, 2014, 42(12):1447-1454. doi: 10.3969/j.issn.0253-2409.2014.12.006 [21] KIM Y J, KWON H J, HEO I, NAM I S, CHO B K, JIN W C, CHA M S, YEO G K. Mn-Fe/ZSM5 as a low-temperature SCR catalyst to remove NOx from diesel engine exhaust[J]. Appl Catal B:Environ, 2012, 126(38):9-21. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=e0f7be5c20849ab0ce6f0c5ca9faa44b [22] XU W, ZHANG G, CHEN H, ZHANG G, HAN Y, CHANG Y, GONG P. Mn/beta and Mn/ZSM-5 for the low-temperature selective catalytic reduction of NO with ammonia:Effect of manganese precursors[J]. Chin J Catal, 2018, 39(1):118-127. https://www.sciencedirect.com/science/article/pii/S1872206717629838 [23] 陈树伟, 闫晓亮, 陈佳琪, 马静红, 李瑞丰.富氧条件下Mn/ZSM-5选择催化CH4还原NO[J].催化学报, 2010, 31(9):1107-1114. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=cuihuaxb201009004CHEN Shu-wei, YAN Xiao-liang, CHEN Jia-qi, MA Jing-hong, LI Rui-feng. Selective catalytic reduction of NO in excess oxygen by methane over Mn/ZSM-5 catalysts[J]. Chin J Catal, 2010, 31(9):1107-1114. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=cuihuaxb201009004 [24] LOU X, LIU P, LI J, LI Z, HE K. Effects of calcination temperature on Mn species and catalytic activities of Mn/ZSM-5 catalyst for selective catalytic reduction of NO with ammonia[J]. Appl Surf Sci, 2014, 307:382-387. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=eca672fd7b0886d0456fa34f89753c36 [25] LI J, CHEN J, KE R, LUO C, HAO J. Effects of precursors on the surface Mn species and the activities for NO reduction over MNOx/TiO catalysts[J]. Catal Commun, 2007, 8(12):1896-1900. https://www.sciencedirect.com/science/article/pii/S1566736707001057 [26] MA L, CHANG H, YANG S, CHEN L, FU L, LI J. Relations between iron sites and performance of Fe/HBEA catalysts prepared by two different methods for NH3-SCR[J]. Chem Eng J, 2012, 209(20):652-660. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=f9692016d8abf69b29167617b3ab7057 [27] GUAN B, LIN H, ZHU L, HUANG Z. Selective catalytic reduction of NOx with NH3 over Mn, Ce substitution Ti0.9V0.1O2-δ nanocomposites catalysts prepared by self-propagating high-temperature synthesis method[J]. J Phys Chem C, 2011, 115(26):12850-12863. [28] YAMASHITA T, HAYES P. Analysis of XPS spectra of Fe2+ and Fe3+ ions in oxide materials[J]. Appl Surf Sci, 2008, 254(8):2441-2449. https://www.sciencedirect.com/science/article/pii/S0169433207013748 [29] YANG S, GUO Y, YAN N, WU D, HE H, QU Z, CHEN Y, ZHOU Q, JIA J. Nanosized cation-deficient Fe-Ti spinel:A novel magnetic sorbent for elemental mercury capture from flue gas[J]. ACS Appl Mater Inter, 2011, 3(2):209-217. http://d.old.wanfangdata.com.cn/NSTLQK/NSTL_QKJJ0220608086/ [30] TRAWCZY ŃSKI J, BIELAK B, MIŚTA W. Oxidation of ethanol over supported manganese catalysts-effect of the carrier[J]. Appl Catal B:Environ, 2005, 55(4):277-285. http://cn.bing.com/academic/profile?id=d4f7c62dee28a8bc8c7c946a492627bc&encoded=0&v=paper_preview&mkt=zh-cn [31] SULTANA A, SASAKI M, HAMADA H. Influence of support on the activity of Mn supported catalysts for SCR of NO with ammonia[J]. Catal Today, 2012, 185(1):284-289. http://cn.bing.com/academic/profile?id=c419c731ff66c8a8c7b4898b2f1a9b9a&encoded=0&v=paper_preview&mkt=zh-cn [32] ZHOU H, SU Y, LIAO W, DENG W, ZHONG F. Preparation, characterization, and properties of monolithic Fe/Al2O3/cordierite catalysts for NO reduction with C2H6[J]. Appl Catal A:Gen, 2015, 505:402-409. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=12e0df30a7ea3c87db69a8aa87b2d676 [33] DĚDEČEK J, ČAPEK L, KAUCKY D, SOBALIÝK Z, WICHTERLOVÁ B. Siting and distribution of the Co ions in Beta zeolite:A UV-Vis-NIR and FTIR study[J]. J Catal, 2002, 211(1):198-207. http://cn.bing.com/academic/profile?id=36be7f762c42a7d457f43fe0b99efc52&encoded=0&v=paper_preview&mkt=zh-cn [34] ČAPEK L, KREIBICH V, DĚDEČEK J, GRYGAR T, WICHTERLOVÁ B, SOBALÍK Z, MARTENS J A, BROSIUS R, TOKAROVÁ V. Analysis of Fe species in zeolites by UV-VIS-NIR, IR spectra and voltammetry. Effect of preparation, Fe loading and zeolite type[J]. Microporous Mesoporous Mater, 2005, 78(1):279-289. http://cn.bing.com/academic/profile?id=9872b495f1e3c86558a670cd1c949c9f&encoded=0&v=paper_preview&mkt=zh-cn [35] SATSUMA A, SHIMIZU K I. In situ FT-IR study of selective catalytic reduction of NO over alumina-based catalysts[J]. Prog Energy Combust Sci, 2003, 29(1):71-84. doi: 10.1016/S0360-1285(02)00033-3 [36] LONG R, YANG R. FTIR and kinetic studies of the mechanism of Fe3+-exchanged TiO2-pillared clay catalyst for selective catalytic reduction of NO with ammonia[J]. J Catal, 2000, 190(1):22-31. [37] MA Q, LIU Y, HE H. Synergistic effect between NO2and SO2 in their adsorption and reaction on γ-alumina[J]. J Phys Chem A, 2008, 112(29):6630-6635. http://med.wanfangdata.com.cn/Paper/Detail/PeriodicalPaper_PM18578482 [38] HADJⅡVANOV K. Identification of neutral and charged NxOy surface species by IR spectroscopy[J]. Catal Rev, 2000, 42(1/2):71-144. [39] LIN Q, LI J, MA L, HAO J. Selective catalytic reduction of NO with NH3 over Mn-Fe/USY under lean burn conditions[J]. Catal Today, 2010, 151(3):251-256. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=f10eb18f990026a3322b08e6ded5d28a [40] WU Z, JIANG B, LIU Y. HAIQIANG WANG A, JIN R, DRIFT study of manganese/titania-based catalysts for low-temperature selective catalytic reduction of NO with NH3[J]. Environ Sci Technol, 2007, 41(16):5812. http://cn.bing.com/academic/profile?id=0cb6b1a8e44d7d7909dc93d138613bf8&encoded=0&v=paper_preview&mkt=zh-cn [41] LONG J, ZHANG Z, DING Z, RUAN R, LI Z, WANG X. Infrared study of the NO reduction by hydrocarbons over iron sites with low nuclearity:Some new insight into the reaction pathway[J]. J Phys Chem C, 2010, 114(37):15713-15727. http://cn.bing.com/academic/profile?id=46577b055a3f2750ae7d9e37446ad18b&encoded=0&v=paper_preview&mkt=zh-cn [42] HANEDA M, KINTAICHI Y, BION N, HAMADA H. Mechanistic study of the effect of coexisting H2O on the selective reduction of NO with propene over sol-gel prepared In2O3-Al2O3 catalyst[J]. Appl Catal B:Environ, 2003, 42(1):57-68. doi: 10.1016/S0926-3373(02)00215-1 [43] PARK J H, PARK H J, BAIK J H, NAM I S, SHIN C H, LEE J H, CHO B K, OH S H. Hydrothermal stability of CuZSM5 catalyst in reducing NO by NH3 for the urea selective catalytic reduction process[J]. J Catal, 2006, 240(1):47-57. http://cn.bing.com/academic/profile?id=013ba3db48ad052845e9ea3b109322dd&encoded=0&v=paper_preview&mkt=zh-cn [44] KUCHEROV A V, MONTREUIL C N, KUCHEROVA T N, SHELEF M. In situ high-temperature ESR characterization of FeZSM-5 and FeSAPO-34 catalysts in flowing mixtures of NO, C3 H6, and O2[J]. Catal Lett, 1998, 56(4):173-181. doi: 10.1023/A:1019002322340 [45] ZHANG Q, LI Y, AN D, WANG Y. Catalytic behavior and kinetic features of FeOx/SBA-15 catalyst for selective oxidation of methane by oxygen[J]. Appl Catal A:Gen, 2009, 356(1):103-111. http://cn.bing.com/academic/profile?id=e41aa1fe50dcd20cff0efb56bbbee29e&encoded=0&v=paper_preview&mkt=zh-cn