Fe x MnCe1-AC低温SCR催化剂SO2中毒机理研究

doi:10.11949/0438-1157.20190318

摘要/Abstract

摘要：

以活性炭为载体，通过超声辅助浸渍法制备了一系列Fe _x MnCe₁-AC催化剂，考察了该系列催化剂的低温NH₃-SCR脱硝活性，确立了活性最佳的催化剂，并探究了SO₂对其脱硝性能的影响。结果表明，Fe_0.1MnCe₁-AC催化剂低温脱硝活性最高，在120~220℃范围内NO的转化率均在90%以上（无SO₂）。此外，在180℃、SO₂浓度为429 mg/m³时，该催化剂仍能保持77%左右的脱硝率。通过BET、XRD、XPS、H₂-TPR、NH₃-TPD、FT-IR、TGA等表征手段对催化剂的SO₂中毒机理进行了分析。研究发现，SO₂能与NH₃及催化剂中金属组分生成硫酸铵盐((NH₄)₂SO₄、(NH₄)₂SO₃)、MnSO₄等物质，改变了原催化剂孔道结构并减少了催化剂表面Br?nsted和Lewis酸性位点，抑制了催化剂吸附NH₃的能力。更多地，SO₂促使催化剂中Mn⁴⁺、Ce³⁺、Fe³⁺和Fe³⁺—OH^-基团数量下降，表面可还原物质减少，从而降低了催化剂的脱硝活性。

关键词: 选择性催化还原, 活性炭, 催化剂, 氮氧化物, 二氧化硫, 中毒机理

Abstract:

A series of Fe _x MnCe₁-AC catalysts were prepared by ultrasonic-assisted impregnation method with activated carbon as carrier. The low-temperature NH₃-SCR denitrification activity of the catalysts was investigated, and the best activity catalyst was established. The effect of SO₂ on its denitration performance was also explored. The results showed that Fe_0.1MnCe₁-AC catalyst exhibited best denitration efficiency at low-temperature among prepared catalysts, the conversion rate of NO exceeded 90% with the temperature range from 120℃ to 220℃ (no SO₂). In addition, the catalyst could maintain NO conversion rate of approximately 77% under the atmosphere of 180℃ and SO₂ concentration of 429 mg/m³. The mechanism of SO₂ poisoning on the catalyst was characterized with BET, XRD, XPS, H₂-TPR NH₃-TPD, FT-IR and TGA. It was observed that SO₂ could form ammonium sulfate ( (NH₄)₂SO₄, (NH₄)₂SO₃), and MnSO₄ with NH₃ and the metal components in the catalyst, which changed the pore structure of the fresh catalyst and reduced the Br?nsted acid sites and Lewis acid sites on the catalyst surface. These variation made the inhibitory effect on the catalytic adsorption capacity of NH₃. Moreover, SO₂ also promoted a decrease in the number of Mn⁴⁺, Ce³⁺, Fe³⁺ and Fe³⁺—OH^- groups in the catalyst, and lessened the surface reducible species, thereby reducing the activity of the catalyst denitration.

Key words: selective catalytic reduction, activated carbon, catalyst, nitric oxide, sulfur dioxide, poisoning mechanism

中图分类号:

TQ 028.8

陈潇雪, 宋敏, 孟凡跃, 卫月星. Fe _x MnCe₁-AC低温SCR催化剂SO₂中毒机理研究[J]. 化工学报, 2019, 70(8): 3000-3010.

Xiaoxue CHEN, Min SONG, Fanyue MENG, Yuexing WEI. Mechanism study on SO₂ poisoning of Fe _x MnCe₁-AC catalyst for low-temperature SCR[J]. CIESC Journal, 2019, 70(8): 3000-3010.

图/表 12

图1 催化剂活性评价装置

Fig.1 Flow process diagram of equipment for evaluation of catalyst activity

图2 不同温度催化剂样品的脱硝活性评价

Fig.2 Catalytic activity of different catalysts with variation of temperature

图3 优选催化剂在含SO2气氛下NO转化率

Fig.3 NO conversion of selected catalyst with presence of SO2

图4 催化剂的N2吸附-脱附等温线和孔径分布

Fig.4 N2 adsorption-desorption isotherms and pore size distribution curves of catalysts

表1 催化剂中毒前后BET比表面积和孔结构特征

Table 1 BET specific surface area and pore characterization of fresh and poisoned catalyst

催化剂	比表面积/(m²/g)	孔容/(cm³/g)	微孔孔容/(cm³/g)	平均孔径/nm
Fe_0.1MnCe₁-AC	766.4	0.7641	0.1478	3.988
180℃-429 mg/m³SO₂	632.5	0.6636	0.1116	4.197
120℃-429 mg/m³SO₂	491.1	0.4985	0.0934	4.060
活性炭	953.5	1.137	0.2017	4.179

图5 催化剂中毒前后的X射线衍射谱图

Fig.5 XRD patterns of fresh and poisoned catalyst

图6 催化剂中毒前后Mn 2p、Fe 2p、Ce 3d的XPS能谱图

Fig.6 XPS of fresh and poisoned catalyst for Mn 2p, Fe 2p and Ce 3d

表2 催化剂表面相关原子价态分布

Table 2 Percentage of different valence states of relative catalytic atom

催化剂

Mn²⁺

Mn³⁺

Mn⁴⁺

Ce³⁺

Ce⁴⁺

Fe_0.1MnCe₁-AC

12.9%

(641.2 eV)

41%

(642.5 eV)

46.1%

(644.1 eV)

53.6%

46.4%

180℃-429 mg/m³ SO₂

7.4%

(641.2 eV)

48.5%

(642 eV)

44.1%

(644.2 eV)

38.4%

61.6%

120℃-429 mg/m³ SO₂

23.5%

(641.2 eV)

48.1%

(642.4 eV)

28.3%

(644.1 eV)

27.7%

72.3%

图7 催化剂中毒前后的H2-TPR图

Fig.7 H2-TPR profiles of fresh and poisoned catalyst

图8 催化剂中毒前后的NH3-TPD曲线

Fig.8 NH3-TPD profiles of fresh and poisoned catalyst

图9 催化剂中毒前后的FT-IR谱图

Fig.9 FT-IR spectra of fresh and poisoned catalyst

图10 催化剂中毒前后的TG/DTG图

Fig.10 TG/DTG curves of fresh and poisoned catalyst

参考文献 44

1	Fang N J , Guo J X , Shu S , et al . Effect of calcination temperature on low-temperature NH₃-SCR activity and the resistance of SO₂ with or without H₂O over Fe-Mn-Zr catalyst[J]. Journal of the Taiwan Institute of Chemical Engineers, 2018, 93: 277-288.
2	Roy S , Hegde M S , Madras G . Catalysis for NO _x abatement[J]. Applied Energy, 2009, 86(11): 2283-2297.
3	Peng Y , Li J , Si W , et al . Insight into deactivation of commercial SCR catalyst by arsenic: an experiment and DFT study[J]. Environmental Science & Technology, 2014, 48(23): 13895-13900.
4	Chen L , Li J , Ge M . 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.
5	Gao F , Tang X , Yi H , et al . Improvement of activity, selectivity and H₂O & SO₂-tolerance of micro-mesoporous CrMn₂O₄ spinel catalyst for low-temperature NH₃-SCR of NO _x [J]. Applied Surface Science, 2019, 466: 411-424.
6	Zhao L , Li C , Zhang X , et al . A review on oxidation of elemental mercury from coal-fired flue gas with selective catalytic reduction catalysts[J]. Catalysis Science & Technology 2015, 5(7): 3459-3472.
7	Nie Y , Yan Q , Chen S , et al . CuTi LDH derived NH₃-SCR catalysts with highly dispersed CuO active phase and improved SO₂ resistance[J]. Catalysis Communications, 2017, 97: 47-50.
8	Nedyalkova R , Kamasamudram K , Currier N W , et al . Experimental evidence of the mechanism behind NH₃ overconsumption during SCR over Fe-zeolites[J]. Journal of Catalysis, 2013, 299: 101-108.
9	Putluru S S R , Schill L , Jensen A D , et al . Mn/TiO₂ and Mn-Fe/TiO₂ catalysts synthesized by deposition precipitation-promising for selective catalytic reduction of NO with NH₃ at low temperatures[J]. Applied Catalysis B: Environmental, 2015, 165: 628-635.
10	Kwon D W , Nam K B , Hong S C . The role of ceria on the activity and SO₂ resistance of catalysts for the selective catalytic reduction of NO _x by NH₃ [J]. Applied Catalysis B: Environmental, 2015, 166/167: 37-44.
11	Zhuang K , Zhang Y P , Huang T J , et al . Sulfur-poisoning and thermal reduction regeneration of holmium-modified Fe-Mn/TiO₂ catalyst for low-temperature SCR[J]. Journal of Fuel Chemistry and Technology, 2017, 45(11): 1356-1364.
12	Leng X , Zhang Z , Li Y , et al . Excellent low temperature NH₃-SCR activity over Mn _a Ce_0.3TiO _x (a = 0.1—0.3) oxides: influence of Mn addition[J]. Fuel Processing Technology, 2018, 181: 33-43.
13	Wang L , Huang B , Su Y , et al . Manganese oxides supported on multi-walled carbon nanotubes for selective catalytic reduction of NO with NH₃: catalytic activity and characterization[J]. Chemical Engineering Journal, 2012, 192: 232-241.
14	Li J H , Chang H Z , Ma L , et al . Low-temperature selective catalytic reduction of NO _x with NH₃ over metal oxide and zeolite catalysts—a review[J].Catalysis Today, 2011, 175: 147-156.
15	Jin R , Liu Y , Wang Y , et al . The role of cerium in the improved SO₂ tolerance for NO reduction with NH₃ over Mn-Ce/TiO₂ catalyst at low temperature[J]. Applied Catalysis B: Environmental, 2014, 148/149: 582-588.
16	Yan D J , Ya Y U , Huang X M , et al . Poisoning effect of SO₂ on Mn-Ce/TiO₂ catalysts for NO reduction by NH₃ at low temperature[J]. Journal of Fuel Chemistry & Technology, 2016, 44(2): 232-238.
17	France L J , Yang Q , Li W , et al . Ceria modified FeMnO _x —enhanced performance and sulphur resistance for low-temperature SCR of NO _x [J]. Applied Catalysis B: Environmental, 2017, 206: 203-215.
18	Cao F , Su S , Xiang J , et al . The activity and mechanism study of Fe-Mn-Ce/γ-Al₂O₃ catalyst for low temperature selective catalytic reduction of NO with NH₃ [J]. Fuel, 2015, 139: 232-239.
19	乔南利, 杨忆新, 刘清龙, 等 . 载体物化性质对锰铈催化剂NH₃-SCR脱硝性能的影响[J]. 燃料化学学报, 2018, 46(6): 733-742.
	Qiao N L , Yang Y X , Liu Q L , et al . Influence of different supports on the physicochemical properties and denitration performance of the supported MnCe-based catalysts for NH₃-SCR[J]. Journal of Fuel Chemistry and Technology, 2018, 46(6): 733-742.
20	Marban G , Valdessolis T , Fuertes A B . Mechanism of low-temperature selective catalytic reduction of NO with NH₃ over carbon-supported Mn₃O₄-role of surface NH₃ species: SCR mechanism[J]. Physical Chemistry Chemical Physics, 2004, 6(2): 453-464.
21	周愉千, 刘超, 宋鹏, 等 . CeO _x /AC催化剂NH₃选择性催化还原NO[J]. 环境工程学报, 2012, 6(8): 2720-2724.
	Zhou Y Q , Liu C , Song P , et al . CeO _x /AC catalysts for selective catalytic reduction of NO by NH₃ [J]. Chinese Journal of Environmental Engineering, 2012, 6(8): 2720-2724.
22	Jin R , Liu Y , Wu Z , et al . Low-temperature selective catalytic reduction of NO with NH₃ over MnCe oxides supported on TiO₂ and Al₂O₃: a comparative study[J]. Chemosphere, 2010, 78(9): 1160-1166.
23	Peña D A , Uphade B S , Smirniotis P G . TiO₂-supported metal oxide catalysts for low-temperature selective catalytic reduction of NO with NH₃ (I): Evaluation and characterization of first row transition metals[J]. Journal of Catalysis, 2004, 221(2): 421-431.
24	Xu L , Li X S , Crocker M , et al . A study of the mechanism of low-temperature SCR of NO with NH₃ on MnO _x /CeO₂ [J]. Journal of Molecular Catalysis A: Chemical, 2013, 378: 82-90.
25	Zhang D , Zhang L , Shi L , et al . In situ supported MnO _x -CeO _x on carbon nanotubes for the low-temperature selective catalytic reduction of NO with NH₃ [J]. Nanoscale, 2013, 5(3): 1127.
26	解智博, 宋艳军, 梁金生, 等 . 锰基催化剂低温选择催化还原处理NO _x 的研究现状与展望[J]. 材料导报, 2017, 31(11): 38-43.
	Xie Z B , Song Y J , Liang J S , et al . Research status and prospects of low temperature selective catalytic reduction of NO _x by MnO _x -based catalysts[J]. Materials Review, 2017, 31(11): 38-43.
27	Li W , Zhang C , Li X , et al . Ho-modified Mn-Ce/TiO₂ for low-temperature SCR of NO with NH₃: evaluation and characterization[J]. Chinese Journal of Catalysis, 2018, 39(10): 1653-1663.
28	Liu Z , Wang A , Wang X , et al . Ir-C xerogels synthesized by sol-gel method for NO reduction[J]. Catalysis Today, 2008, 137(2/3/4): 162-166.
29	Lu X , Song C , Jia S , et al . Low-temperature selective catalytic reduction of NO _x with NH₃ over cerium and manganese oxides supported on TiO₂-graphene[J]. Chemical Engineering Journal, 2015, 260: 776-784.
30	Zhang X M , Deng Y Q , Tian P , et al . Dynamic active sites over binary oxide catalysts: in situ/operando spectroscopic study of low-temperature CO oxidation over MnO _x -CeO₂ catalysts[J]. Applied Catalysis B: Environmental, 2016, 191: 179-191.
31	Miller D D , Chuang S S C . In situ infrared study of NO reduction over Pd/Al₂O₃ and Ag-Pd/Al₂O₃ catalysts under H₂-rich and lean-burn conditions[J]. Journal of the Taiwan Institute of Chemical Engineers, 2009, 40(6): 613-621.
32	Xu W , He H , Yu Y . Deactivation of a Ce/TiO₂ catalyst by SO₂ in the selective catalytic reduction of NO by NH₃ [J]. Journal of Physical Chemistry C, 2009, 113(11): 4426-4432.
33	Qiao J , Wang N , Wang Z , et al . Porous bimetallic Mn₂Co₁O _x catalysts prepared by a one-step combustion method for the low temperature selective catalytic reduction of NO _x with NH₃ [J]. Catalysis Communications, 2015, 72: 111-115.
34	Kapteijn F , Singoredjo L , Andreini A , et al . Activity and selectivity of pure manganese oxides in the selective catalytic reduction of nitric oxide with ammonia[J]. Cheminform, 1994, 3(2/3): 173-189.
35	Shen B , Liu T , Zhao N , et al . Iron-doped Mn-Ce/TiO₂ catalyst for low temperature selective catalytic reduction of NO with NH₃ [J]. Journal of Environmental Sciences, 2010, 22(9): 1447-1454.
36	Mukundan D , Oliver K , Martin E , et al . Characterization and catalytic investigation of Fe-ZSM₅ for urea-SCR[J]. Catalysis Today, 2007, 119(1/2/3/4): 137-144.
37	Zhou X , Huang X , Xie A , et al . V₂O₅-decorated Mn-Fe/attapulgite catalyst with high SO₂ tolerance for SCR of NO _x with NH₃ at low temperature[J]. Chemical Engineering Journal, 2017, 326: 1074-1085.
38	Lin X , Li S , He H , et al . Evolution of oxygen vacancies in MnO _x -CeO₂ mixed oxides for soot oxidation[J]. Applied Catalysis B: Environmental, 2017, 223: 91-102.
39	Li Y , Wan Y , Li Y P , et al . Low-temperature selective catalytic reduction of NO with NH₃ over Mn₂O₃-doped Fe₂O₃ hexagonal microsheets[J]. ACS Applied Materials & Interfaces, 2016, 8(8): 5224-5233.
40	Raj A M E , Victoria S G , Jothy V B , et al . XRD and XPS characterization of mixed valence Mn₃O₄ hausmannite thin films prepared by chemical spray pyrolysis technique[J]. Applied Surface Science, 2010, 256(9): 2920-2926.
41	Yang J , Su Z , Ren S , et al . Low-temperature SCR of NO with NH₃ over biomass char supported highly dispersed Mn-Ce mixed oxides[J]. Journal of the Energy Institute, 2019: 92(4): 883-891.
42	Shen B X , Liu T . Deactivation of MnO _x -CeO _x /ACF catalysts for low-temperature NH₃-SCR in the presence of SO₂ [J]. Acta Physico-Chimica Sinica, 2010, 26(11): 3009-3016.
43	Shi Y , Pan H , Zhang Y , et al . Promotion of MgO addition on SO₂ tolerance of Ag/Al₂O₃ for selective catalytic reduction of NO _x with methane at low temperature[J]. Catalysis Communications, 2008, 9(5): 796-800.
44	Zhu Z , Niu H , Liu Z , et al . Decomposition and reactivity of NH₄HSO₄ on V₂O₅/AC catalysts used for NO reduction with ammonia[J]. Journal of Catalysis, 2000, 195(2): 268-278.

[1]	米泽豪, 花儿. 基于DFT和COSMO-RS理论研究多元胺型离子液体吸收SO₂气体[J]. 化工学报, 2023, 74(9): 3681-3696.
[2]	李艺彤, 郭航, 陈浩, 叶芳. 催化剂非均匀分布的质子交换膜燃料电池操作条件研究[J]. 化工学报, 2023, 74(9): 3831-3840.
[3]	陈杰, 林永胜, 肖恺, 杨臣, 邱挺. 胆碱基碱性离子液体催化合成仲丁醇性能研究[J]. 化工学报, 2023, 74(9): 3716-3730.
[4]	范孝雄, 郝丽芳, 范垂钢, 李松庚. LaMnO₃/生物炭催化剂低温NH₃-SCR催化脱硝性能研究[J]. 化工学报, 2023, 74(9): 3821-3830.
[5]	杨学金, 杨金涛, 宁平, 王访, 宋晓双, 贾丽娟, 冯嘉予. 剧毒气体PH₃的干法净化技术研究进展[J]. 化工学报, 2023, 74(9): 3742-3755.
[6]	杨欣, 彭啸, 薛凯茹, 苏梦威, 吴燕. 分子印迹-TiO₂光电催化降解增溶PHE废水性能研究[J]. 化工学报, 2023, 74(8): 3564-3571.
[7]	吕龙义, 及文博, 韩沐达, 李伟光, 高文芳, 刘晓阳, 孙丽, 王鹏飞, 任芝军, 张光明. 铁基导电材料强化厌氧去除卤代有机污染物：研究进展及未来展望[J]. 化工学报, 2023, 74(8): 3193-3202.
[8]	李锦潼, 邱顺, 孙文寿. 煤浆法烟气脱硫中草酸和紫外线强化煤砷浸出过程[J]. 化工学报, 2023, 74(8): 3522-3532.
[9]	杨菲菲, 赵世熙, 周维, 倪中海. Sn掺杂的In₂O₃催化CO₂选择性加氢制甲醇[J]. 化工学报, 2023, 74(8): 3366-3374.
[10]	李凯旋, 谭伟, 张曼玉, 徐志豪, 王旭裕, 纪红兵. 富含零价钴活性位点的钴氮碳/活性炭设计及甲醛催化氧化应用研究[J]. 化工学报, 2023, 74(8): 3342-3352.
[11]	屈园浩, 邓文义, 谢晓丹, 苏亚欣. 活性炭/石墨辅助污泥电渗脱水研究[J]. 化工学报, 2023, 74(7): 3038-3050.
[12]	李盼, 马俊洋, 陈志豪, 王丽, 郭耘. Ru/α-MnO₂催化剂形貌对NH₃-SCO反应性能的影响[J]. 化工学报, 2023, 74(7): 2908-2918.
[13]	余娅洁, 李静茹, 周树锋, 李清彪, 詹国武. 基于天然生物模板构建纳米材料及集成催化剂研究进展[J]. 化工学报, 2023, 74(7): 2735-2752.
[14]	涂玉明, 邵高燕, 陈健杰, 刘凤, 田世超, 周智勇, 任钟旗. 钙基催化剂的设计合成及应用研究进展[J]. 化工学报, 2023, 74(7): 2717-2734.
[15]	张琦钰, 高利军, 苏宇航, 马晓博, 王翊丞, 张亚婷, 胡超. 碳基催化材料在电化学还原二氧化碳中的研究进展[J]. 化工学报, 2023, 74(7): 2753-2772.

Fe _x MnCe₁-AC低温SCR催化剂SO₂中毒机理研究

Mechanism study on SO₂ poisoning of Fe _x MnCe₁-AC catalyst for low-temperature SCR

RichHTML

PDF (PC)

可视化

摘要/Abstract

引用本文

使用本文

图/表 12

参考文献 44

相关文章 15

编辑推荐

Metrics

本文评价