甲烷在金属铁及氧化铁表面还原NO的研究

苏亚欣; 任立铭; 苏阿龙; 邓文义

甲烷在金属铁及氧化铁表面还原NO的研究

东华大学环境科学与工程学院, 上海 201620

基金项目: 国家自然科学基金(51278095);上海市自然科学基金(11ZR1401000)。

详细信息

通讯作者:
苏亚欣(1972- ),男,博士,副教授,E-mail:suyx@dhu.edu.cn,Tel:021-67792552。

中图分类号: X511
计量
- 文章访问数: 1382
- HTML全文浏览量: 18
- PDF下载量: 614
- 被引次数: 0
出版历程
- 收稿日期: 2013-03-25
- 修回日期: 2013-05-02
- 刊出日期: 2013-11-30

NO reduction by methane on the surface of iron and iron oxides

School of Environmental Science and Engineering, Donghua University, Shanghai 201620, China

摘要

摘要: 在程序控温电加热水平陶瓷管反应器、N₂气氛和模拟烟气气氛及300~1 100℃时,对甲烷在金属铁及其氧化铁表面还原NO的特性进行了实验研究。为使甲烷在脱硝反应后完全燃尽以及脱硝反应过程生成的CO等中间产物完全燃尽,在第一段加热炉后串联了第二段加热炉,补充氧气,实现燃尽。结果表明,甲烷在金属铁及氧化铁表面能够高效地还原NO。在N₂气氛中,在900℃以上温度范围内甲烷在金属铁表面的脱硝效率超过95%,与甲烷在氧化铁表面的脱硝效率差别很小。在模拟烟气条件下,当过量空气系数小于1.0时,在900℃以上时,甲烷在金属铁和氧化铁表面的脱硝效率都能超过90%,且未燃尽和燃尽两种条件下NO的还原率相差不大。NO同时通过金属铁的直接还原和甲烷的再燃还原两种反应机理脱除。而甲烷则通过还原氧化铁为金属铁,从而使金属铁直接还原NO可持续进行。同时,甲烷再燃反应的中间产物HCN/NH₃等被氧化铁还原,从而使燃尽后的脱硝效率不下降。研究结果表明,甲烷和金属铁或氧化铁在富燃料条件下可有效地还原NO。
- NO还原 /
- 甲烷 /
- 铁 /
- 氧化铁
Abstract: NO reduction by methane on the surface of iron and iron oxides was experimentally investigated in a one-dimensional temperature-programmed ceramic tubular reactor at 300~1 100℃ in both nitrogen and simulated flue gas atmospheres. To ensure that the residual methane after NO reduction and the intermediates (e.g. CO) formed during the NO reduction were completely burned out, a second furnace with a supply of O₂ was connected in series after the first furnace. The results indicated that methane can effectively reduce NO to N₂ over the surface of metallic iron and iron oxides. In N₂ atmosphere, more than 95% of NO is reduced by methane over metallic iron at a temperature above 900℃, which is very close to that for NO reduction over iron oxides. In the simulated flue gas atmosphere with an excessive air ratio being lower than 1.0, more than 90% of NO is reduced by methane over both metallic iron and iron oxides at a temperature above 900℃; there is little difference in NO reduction under both burnout or non-burnout conditions. NO is reduced simultaneously via two routes, i.e. the direct reduction by metallic iron and the reduction by reburning of methane. Iron oxides are reduced to metallic iron by methane through partial oxidation over iron oxides to maintain the sustainable reduction of NO by metallic iron. At the same time, the intermediate products during NO reduction by methane such as HCN/NH₃ are converted by iron oxides, which prevent the NO reduction efficiency from dropping after burnout. The present results then prove that methane can effectively reduce NO over iron or iron oxides under fuel rich condition.
- NO reduction /
- methane /
- iron /
- iron oxides

HTML全文

参考文献(19)

马风哪, 程伟琴.国内火电厂氮氧化物排放现状及控制技术探讨[J]. 广州化工, 2011, 39(15): 57-59. (MA Feng-na, CHENG Wei-qin. The discharge status and controlling measures of nitrogen oxides of thermal power plants in China[J]. Guangzhou Chemical Industry, 2011, 39(15): 57-59.)

PARVULESCU V I, GRANGE P, DELMON B. Catalytic removal of NO[J]. Catal Today, 1998, 46(4): 233-316.

JANSSEN F, MEIJER R. Quality control of DeNO_x catalysts performance testing, surface analysis and characterization of DeNO_x catalysts[J]. Catal Today, 1993, 16(2): 157-185.

CENTI G, PERATHONER S. Introduction: State of the art in the development of catalytic processes for the selective catalytic reduction of NO_x into N₂[J]. Stud Surf Sci Catal, 2007, 171: 1-24.

BETHKE KA, KUNG M C, YANG B, SHAH M, ALT D, LI C, KUNG H H. Metal oxide catalysts for lean NO_x reduction[J]. Catal Today, 1995, 26(2):169-183.

BETHKE K A, ALT D, KUNG M C. NO reduction by hydrocarbons in an oxidizing atmosphere over transition metal-zirconium mixed oxides[J]. Catal Lett, 1994, 25(1/2): 37-48.

ILIOPOULOU E F, EVDOU A P, LEMONIDOU A A, VASALOS I A. Ag/alumina catalysts for the selective catalytic reduction of NO_<em>x using various reductants[J]. Appl Catal A: Gen, 2004, 274(1/2): 179-189.

KOTSIFA A, KONDARIDES D I, VERYKIOS X E. A comparative study of the selective catalytic reduction of NO by propylene over supported Pt and Rh catalysts[J]. Appl Catal B: Environ, 2008, 80(3/4): 260-270.

LIU Z, WANG K, ZHANG X, WANG J, CAO H, GONG M, CHEN Y. Study on methane selective catalytic reduction of NO on Pt/Ce_0.67Zr_0.33O₂ and its application[J]. J Nat Gas Chem, 2009, 18(1): 66-70.

GRADON B, LASEK J. Investigation of reduction of NO to N₂ by reaction with Fe[J]. Fuel, 2010, 89(11): 3505-3509.

苏亚欣, 苏阿龙, 成豪. 金属铁直接催化还原NO的实验研究[J]. 煤炭学报, 2013, 38(S1):206-210. (SU Ya-xin, SU A-long, CHENG Hao. Experimental study on direct catalytic reduction of NO by metallic iron[J]. Journal of China Coal Society, 2013, 38(s1): 206-210.)

李然家, 沈师孔. 晶格氧用于甲烷氧化制合成气的研究-氧化铁的氧化还原性能[J]. 分子催化, 2001, 3(15): 181-186. (LI Ran-jia, SHENG Shi-kong. Study on lattice oxygen used in the conversion of methane to synthesis gas-redox performance of Fe₂O₃ catalyst[J]. Journal of Molecular Catalysis(China), 2001, 3(15): 181-186.)

NAKAYAMA O, IKENAGA N, MIYAKE T, YAGASAKI E, SUZUKI T. Production of synthesis gas from methane using lattice oxygen of NiO-Cr₂O₃-MgO complex oxide[J]. Ind Eng Chem Res, 2010, (492): 526-534.

王华, 魏永刚. 晶格氧部分氧化甲烷制取合成气技术[M]. 北京: 冶金工业出版社, 2009: 88. (WANG Hua, WEI Yong-gang. Partial oxidation of methane by lattice oxygen to produce synthesis gas[M]. Beijing: Metallurgical Industry Press, 2009.)

苏亚欣, 邓文义, 苏阿龙. 甲烷在氧化铁表面还原NO的特性与反应机理研究[J]. 燃料化学学报, 2013, 41(9): 1129-1135. (SU Ya-xin, DENG Wen-yi, SU A long. NO reduction by methane over iron oxides and the mechanism. Journal of Fuel Chemistry and Technology, 2013, 41(9): 1129-1135.)

SMOOT L D, HILL S C, XU H. NO_x control through reburning[J]. Prog Energy Combus Sci, 1998, 24(5): 385-408.

苏亚欣, GATHITU B B, CHEN W Y. Fe₂O₃控制再燃脱硝中间产物HCN的实验研究[J]. 环境科学学报, 2011, 31(6): 1181-1186. (SU Ya-xin, GATHITU B B, CHEN W Y. Experimental examination of HCN compound control by Fe₂O₃ during reburning processes[J]. Acta Scientiae Circumstantiae, 2011, 31(6): 1181-1186.)

TAN H Z, WANG X B, NIU Y Q, LIU H Y, WANG C L, XU T M. Studies of intereaction mechanism between iron and HCN[J]. Asian J Chem, 2010, 22(5): 4017-4025.

陈庚. 气基还原氧化铁动力学机理研究[D]. 大连: 大连理工大学, 2011. (CHENG Geng. The kinetics of the gas-based reduction of iron oxide[D]. Dalian: Dalian University of Technology, 2011.)

施引文献

资源附件(0)

访问统计