电厂烟气脱硝催化剂V2O5-WO3/TiO2失活机理研究

于艳科; 何炽; 陈进生; 孟小然

电厂烟气脱硝催化剂V₂O₅-WO₃/TiO₂失活机理研究

于艳科^1,2,
何炽¹,
陈进生^1,,
孟小然^1,2

1.
中国科学院城市环境研究所, 福建厦门 361021;
2.
中国科学院研究生院, 北京 100049

基金项目: 宁波市科技创新团队项目(201182001); 福建省自然科学基金面上项目(2011J01060)。

详细信息

通讯作者:
陈进生,Tel0592-6190765,E-mail:jschen@iue.ac.cn

中图分类号: O643.36⁺3
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出版历程
- 收稿日期: 2012-05-31
- 修回日期: 2012-08-03
- 刊出日期: 2012-11-30

Deactivation mechanism of de-NO_x catalyst (V₂O₅-WO₃/TiO₂) used in coal fired power plant

1.
Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China;
2.
Graduate University of Chinese Academy of Sciences, Beijing 100049, China

摘要

摘要: 分别以某电厂失活和新鲜的烟气选择性催化还原(SCR)脱硝催化剂为研究对象,模拟测试催化剂的脱硝效率,并采用扫描电子显微镜-能量色散X射线光谱(SEM-EDX)、X荧光光谱(XRF)、X光电子能谱(XPS)、氮气吸脱附、傅里叶红外光谱(FT-IR)、X射线衍射(XRD)和热重分析(TG)等手段对催化剂的微观结构和表面形态进行表征,探讨了SCR催化剂的失活机制。结果表明,380℃下失活催化剂的脱硝效率(35.0%)和比表面积(1.05 m²/g)明显低于新鲜催化剂(88.2%,72.50 m²/g)。与新鲜催化剂相比,失活催化剂中V⁵⁺的比例由17.4%升高到32.2%,并且表面出现了大量的Al₂(SO₄)₃。另外,SEM和XRD结果表明,失活催化剂出现了烧结。催化剂表面V价态的改变、高温烧结和表面Al₂(SO₄)₃相的大量生成是催化剂失活的主要原因。
- 燃煤电厂 /
- 选择性催化还原 /
- 催化剂 /
- 失活机理 /
- 硫酸铝
Abstract: The fresh and deactivated Selective Catalytic Reduction (SCR) catalysts used in a coal fired power plant were studied in a fixed bed reactor. The physical-chemical properties of the catalysts were characterized by means of SEM-EDX, XRF, XPS, N₂ adsorption/desorption, FT-IR, XRD and TG. The results showed that the used catalyst was seriously deactivated. The NO_x removal efficiency and the specific surface area of the used catalyst (35.0%, 1.05 m²/g) were obviously less than those of the fresh catalyst (88.2%, 72.50 m²/g). The V⁵⁺ content in the deactivated catalyst was increased from 17.4% to 32.2% compared with the fresh one, and large quantities of Al₂(SO₄)₃ can be found over the surface of the deactivated catalyst. The results of SEM and XRD showed that the thermal sintering occurred in the deactivated catalyst. Generally, the V₂O₅-WO₃/TiO₂ catalyst deactivation can be interpreted by the valence change of V atoms, thermal sintering and aluminum sulfate formation over catalyst surface.
- coal fired power plant /
- SCR /
- catalyst /
- deactivation mechanism /
- aluminum sulfate

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参考文献(22)

中华人民共和国环境保护部. 2010年环境统计年报[DB/OL]. http://zls.mep.gov.cn/hjtj/nb/2010tjnb/201201/ t20120118_222725. htm, 2012-5-25. (Ministry of Environmental Protection of the People’s Republic of China. 2010 Annual statistics report on environment in China[DB/OL]. http://zls.mep.gov.cn/hjtj/nb/2010tjnb/201201/t20120118_222725.htm, 2012 -5-25)

陈进生. 火电厂烟气脱硝技术——选择性催化还原法[M]. 北京: 中国电力出版社, 2008. (CHEN Jin-sheng. The de-NO_x technology in the power plant——Selective catalytic reduction[M]. Beijing: China Electric Power Press, 2008.)

云端, 宋蔷, 姚强. V₂O₅-WO₃/TiO₂ SCR催化剂的失活机理及分析[J]. 煤炭转化, 2009, 32(1): 91-96. (YUN Duan, SONG Qiang, YAO Qiang. Mechanism and analysis of SCR catalyst deactivation[J]. Coal Conversion, 2009, 32(1): 91-96.)

云端, 邓斯理, 宋蔷, 姚强. V₂O₅-WO₃/TiO₂系SCR催化剂的钾中毒及再生方法[J]. 环境科学研究, 2009, 22(6): 730-735. (YUN Duan, DENG Si-li, SONG Qiang,YAO Qaing. Potassium deactivation and regeneration method of V₂O₅-WO₃/TiO₂ SCR catalyst[J]. Research of Environmental Sciences, 2009, 22(6): 730-735.)

沈伯雄, 熊丽仙, 刘亭, 王静, 田晓娟. 纳米负载型V₂O₅-WO₃/TiO₂催化剂碱中毒及再生研究[J]. 燃料化学学报, 2010, 38(1): 85-90. (SHEN Bo-xiong, XIONG Li-xian, LIU Ting, WANG Jing, TIAN Xiao-juan. Alkali deactivation and regeneration of nano V₂O₅-WO₃/TiO₂ catalysts[J]. Journal of Fuel Chemistry and Technology, 2010, 38(1): 85-90.)

KAMATA H,TAKAHASHI K,ODENBRAND C U I. The role of K₂O in the selective reduction of NO with NH₃ over a V₂O₅ (WO₃)/TiO₂ commercial selective catalytic reduction catalyst[J]. J Mol Catal A, 1999, 139(2/3):189-198.

姜烨, 高翔, 杜学森, 毛剑宏, 骆仲泱, 岑可法. 钾盐对V₂O₅/TiO₂催化剂NH₃选择性催化还原 NO 反应的影响[J]. 中国电机工程学报, 2008, 28(35):21-26. (JIANG Ye, GAO Xiang, DU Xue-sen, MAO Jian-hong, LUO Zhong-yang, CEN Ke-fa. Effects of potassium salts on selective catalytic reduction of NO with NH₃ over V₂O₅/TiO₂ catalysts[J]. Proceedings of the CSEE, 2008, 28(35): 21-26.)

ZHENG Y, JENSEN A D, JOHNSSON J E. Deactivation of V₂O₅-WO₃-TiO₂ SCR catalyst at a biomass-fired combined heat and power plant[J]. Appl Catal B, 2005, 60(3): 253-264.

商雪松, 陈进生, 赵金平, 张福旺, 徐亚, 徐琪. SCR脱硝催化剂失活及其原因研究[J]. 燃料化学学报, 2011, 39(6): 465-470. (SHAN Xue-song, CHEN Jin-sheng, ZHAO Jin-ping, ZHANG Fu-wang, XU Ya, XU Qi. Discussion on the deactivation of SCR denitrification catalyst and its reasons[J]. Journal of Fuel Chemistry and Technology, 2011, 39(6): 465-470.

LARESE C, GALISTEO F C, GRANADOS M L, MARISCAL R, FIERRO J L G, FURIÓ M, RUIZ R F. Deactivation of real three way catalysts by CePO₄ formation[J]. Appl Catal B, 2003, 40(4): 302-317.

NOVA I, ACQUAL D, LIETTI L, GIAMELLO E, FORZATTI P. Study of thermal deactivation of a de-NOx commercial catalyst[J]. Appl Catal B, 2001, 35(1): 31-42.

张汝松, 李志国, 张雷. 选择性催化还原脱硝催化剂生产技术[J]. 工业催化, 2011, 19(8): 7-10. (ZHANG Ru-song, LI Zhi-guo, ZHANG Lei. Production technology of SCR DeNOx catalysts[J]. Industrial Catalysis, 2011, 19(8): 7-10.)

PAGANINI M C, ACQUA L D, GIAMELLO E, LIETTI L, FORZATTI P, BUSCA G. An EPR study of the surface chemistry of the V₂O₅-WO₃/TiO₂ catalyst: Redox behaviour and state of V(IV)[J]. J Catal, 1997, 166(2):195-205.

王幸宜.催化剂表征[M]. 上海: 华东理工大学出版社, 2008: 23-30. (WANG Xing-yi. The characterizations of catalyst[M]. Shanghai: East China University of Science and Technology Press, 2008: 23-30.)

HUANG Z, ZHU Z, LIU Z, LIU Q.Formation and reaction of ammonium sulfate salts on V₂O₅/AC catalyst during selective catalytic reduction of nitric oxide by ammonia at low temperatures[J]. J Catal, 2003, 214(2): 213-219.

STREGE J R, ZYGARLICKE C J, FOLKEDAHL B C, MCCOLLOR D P. SCR deactivation in a full-scale cofired utility boiler[J]. Fuel, 2008, 87(7): 1341-1347.

CROCKER C R, BENSON S A, LAUMB J D. SCR catalyst blinding due to sodium and calcium sulfate formation[J]. Prep Pap Am Chem Soc Div Fuel Chem, 2004, 49(1): 169-170.

NAM I S, ELDRIDGE J W, KITTRELL J. Deactivation of a vanadia-alumina catalyst for nitric oxide reduction by ammonia[J]. Ind Eng Chem Prod Res Dev, 1986, 25(2): 192-197.

SOH B W,NAM I S. Effect of support morphology on the sulfur tolerance of V₂O₅/Al₂O₃ catalyst for the reduction of NO by NH₃[J]. Ind Eng Chem Res, 2003, 42(13): 2975-2986.

MOWERY D L, McCORMICK R L. Deactivation of alumina supported and unsupported PdO methane oxidation catalyst: The effect of water on sulfate poisoning[J]. Appl Catal B, 2001, 34(4): 287-297.

CABELLO GALISTEO F, LARESE C, MARISCAL R, LÓPEZ GRANADOS M, FIERRO J L G, FERNÁNDEZ-RUIZ R, FURIO M. Deactivation on vehicle-aged diesel oxidation catalysts[J]. Top Catal, 2004, 30(1): 451-456.

YU T C, SHAW H. The effect of sulfur poisoning on methane oxidation over palladium supported on γ-alumina catalysts[J]. Appl Catal B, 1998, 18(1/2): 105-114.

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