采用悬浮浆液法将凹凸棒石( PG)涂覆于堇菁石( CC)表面,制备PG-CC载体.将PG-CC载体以过饱和浸渍法经Mn( NO3 ) 2前驱体溶液处理后依次干燥、煅烧制得Mnx/PG-CC整体式催化剂,应用于柴油车尾气净化处理.考察了制备参数(锰负载量、煅烧温度)和工况条件(氧气含量,CH4/NO)对Mnx/PG-CC催化剂在CH4-SCR反应中脱硝活性的影响.采用BET、FE-SEM、XRD、XPS和NO吸脱附等表征手段对催化剂的结构和形貌进行表征.结果表明,在锰负载量为11%、煅烧温度为300℃下所制得的催化剂具有较佳的CH4-SCR脱硝活性,O2含量为5%、CH4/NO为1,反应温度为300 ℃时反应条件最优.锰氧化物活性组分在催化剂表面的高度分散和均匀分布有利于催化剂的CH4-SCR脱硝活性提高,且有助于NO吸附在载体表面并形成硝酸盐中间体参与催化反应.
Cordierite honeycomb ceramic ( CC) was immersed in Palygorskite ( PG)-water mixed slurry to prepare a Palygorskite( PG) coated CC as catalysts′ carrier ( PG-CC) . PG-CC carrier was then treated into a manganese nitrate solution as precursor followed by drying and incineration to obtain Mnx/PG-CC catalysts for diesel exhaust treatment. The effects of the preparation parameters ( manganese oxide content, calcination temperature ) and operation conditions ( oxygen content, CH4/NO) on the performance of the monolith catalysts for CH4-SCR were also investigated. Catalysts were characterized by BET,XRD,FE-SEM and Adsorption and TPD profiles of NO. It was observed that the catalyst calcined at 300 ℃ with 11 wt% of manganese (Mn11/PG-CC(300 ℃)) showed the best CH4-SCR activity when tested at 300℃with a CH4/NO ratio at 1 and 5 vol% O2 presented. manganese oxide active specie was observed to be highly dispersed on the catalyst′s surface, which is benificial for the CH4-SCR activity of the catalyst mainly due to the enhancement of NO adsorption and formation of surface nitrate as active mediate for SCR.
参考文献
| [1] | 李滨;王虹*;丁福臣;李翠清*;宋永吉;柯明;任翠涛.制备方法对Co-MOR催化剂CH4选择还原NO性能的影响[J].物理化学学报,2013(6):1289-1296. |
| [2] | 侯芳.影响我国北方城市PM10超标的主要因素及防治对策探究[J].绿色科技,2015(02):230-231,234. |
| [3] | 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(9):1107-1114. |
| [4] | Li, Yongfeng;Su, Jiaojiao;Ma, Jinghong;Yu, Feng;Chen, Jiaqi;Li, Ruifeng.Novel straight synthesis of super-microporous Cu/Al2O3 catalyst with high CH4-SCR-NO activity[J].Catalysis Communications,2015:6-9. |
| [5] | 张惠 .甲烷选择性催化还原氮氧化物的基础研究[D].浙江大学,2005. |
| [6] | Alicia V.Boix;Juan M.Zamaro;Eduardo A.Lombardo;Eduardo E.Miro.The beneficial effect of silica on the activity and thermal stability of PtCoFerrierite-washcoated cordierite monoliths for the SCR of NO_x with CH_4[J].Applied Catalysis, B. Environmental: An International Journal Devoted to Catalytic Science and Its Applications,20031(1):121-132. |
| [7] | 房华;蔡黎;刘萍;赵明;张丽娟;龚茂初;陈耀强.整体式Pt基催化剂上CH4选择性催化还原NO的研究[J].物理化学学报,2006(8):1004-1009. |
| [8] | 王晓红;黄伟;谢克昌.甲烷活化及转化催化剂研究进展[J].煤炭转化,2001(1):27-31. |
| [9] | 陈一杰 .柴油车用NH3--SCR催化剂去除NOx的催化性能研究[D].浙江工业大学,2014. |
| [10] | 陈春波;李平;隋志军;王寅;朱连利;赫崇衡.大比表面积高牢固度堇青石蜂窝涂层的制备[J].工业催化,2010(3):40-45. |
| [11] | 时博文 .凹凸棒石负载过渡金属氧化物低温SCR胶硝催化剂的制备与表征[D].合肥工业大学,2012. |
| [12] | 张先龙;郭勇;张恒建;解城华;吴雪平.助剂Fe添加对柱状MnOx/PG-AC催化剂低温选择性催化还原（SCR）性能影响[J].环境化学,2015(8):1535-1544. |
| [13] | Lei Ma;Junhua Li;Hamidreza Arandiyan.Influence of calcination temperature on Fe/HBEA catalyst for the selective catalytic reduction of NO_x with NH3[J].Catalysis Today,20121(1):145-152. |
| [14] | 林绮纯;林维明;郝吉明;李俊华.反应条件对Cu/Al-Ce-PILC上丙烯选择性催化还原NO反应的影响[J].催化学报,2006(8):713-718. |
| [15] | Peng Yuan;Peter D.Southon;Zongwen Liu.Functionalization of Halloysite Clay Nanotubes by Grafting with gamma-Aminopropyltriethoxysilane[J].The journal of physical chemistry, C. Nanomaterials and interfaces,200840(40):15742-15751. |
| [16] | Xiaohai Li;Shule Zhang;Yong Jia;Xiaoxiao Liu;Qin Zhong.Selective catalytic oxidation of NO with O2 over Ce-doped MnOx/TiO2 catalysts[J].天然气化学（英文版）,2012(01):17-24. |
| [17] | Wu, Z.;Tang, N.;Xiao, L.;Liu, Y.;Wang, H..MnO_x/TiO_2 composite nanoxides synthesized by deposition-precipitation method as a superior catalyst for NO oxidation[J].Journal of Colloid and Interface Science,20101(1):143-148. |
| [18] | Thirupathi, B.;Smirniotis, P.G..Nickel-doped Mn/TiO _2 as an efficient catalyst for the low-temperature SCR of NO with NH _3: Catalytic evaluation and characterizations[J].Journal of Catalysis,2012:74-83. |
| [19] | Boxiong Shen;Xiaopeng Zhang;Hongqing Ma;Yan Yao;Ting Liu.A comparative study of Mn/CeO2, Mn/ZrO2 and Mn/Ce-ZrO2 for low temperature selective catalytic reduction of NO with NH3 in the presence of SO2 and H2O[J].环境科学学报（英文版）,2013(04):791-800. |
| [20] | Vannice MA.;Zhang X.;Walters AB..THE KINETICS OF NOX DECOMPOSITION AND NO REDUCTION BY CH4 OVER LA2O3 AND SR/LA2O3[J].Journal of Catalysis,19961(1):119-126. |
| [21] | 张志翔 .富氧条件下低温选择性催化丙烯还原氮氧化物的研究[D].上海交通大学,2010. |
| [22] | Ning Li;Aiqin Wang;Zhimin Liu;Xiaodong Wang;Mingyuan Zheng.On the catalytic nature of Mn/sulfated zirconia for selective reduction of NO with methane[J].Applied Catalysis, B. Environmental: An International Journal Devoted to Catalytic Science and Its Applications,20063/4(3/4):292-298. |
| [23] | Tatsuji Yamashita;Albert Vannice.Temperature-programmed desorption of NO adsorbed on Mn_2O_3 and Mn_3O_4[J].Applied Catalysis, B. Environmental: An International Journal Devoted to Catalytic Science and Its Applications,19972(2):141-155. |
| [24] | Kijlstra WS.;Poels EK.;Bliek A.;Brands DS..MECHANISM OF THE SELECTIVE CATALYTIC REDUCTION OF NO BY NH3 OVER MNOX/AL2O3 .1. ADSORPTION AND DESORPTION OF THE SINGLE REACTION COMPONENTS[J].Journal of Catalysis,19971(1):208-218. |
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