采用不同的钾盐前体制备了一系列K/CeO2催化剂,利用热重和程序升温氧化(TPO)等技术考察了其催化性能及稳定性.结果表明,K/CeO2催化剂可使碳黑完全燃烧温度降低近200 ℃.钾盐前体对催化活性和稳定性具有较大影响,由于硝酸钾熔点低,金属在载体上的流动性强,有利于催化剂与碳黑的有效接触,因而表现了较高的活性,三次TPO循环试验中催化活性稳定.碳酸钾的熔点高且碱性较强,使碳黑燃烧生成的CO2不可逆吸附在其表面,导致反应活性低,TPO循环实验表明其反应速率降低,失活明显.
A series of CeO2 supported potassium nitrate and carbonate catalysts were prepared by an impregnation method.The catalytic activity and stability for soot oxidation were investigated by thermal gravimetric/differential thermal analysis and temperature-programmed oxidation cycle techniques.K/CeO2 substantially promotes the catalytic activity,which can be gauged by the lowering of the soot total removal temperature by more than 200 ℃ compared with the uncatalyzed reaction.The influence of K precursor on the catalytic activity and stability was addressed.The effect is discussed in terms of the combined functions ofK and CeO2,potassium mobility and basicity.For potassium-promoted ceria catalysts the potassium nitrate can preserve the high catalytic activity and good stability through several cycles.When K was present as K2CO3,the activity and stability of catalyst were lower than those of KNO3/CeO2.This behavior is attributed to the higher melting point and stronger basicity of K2CO3 which lead to irreversible adsorption of CO2 generated during soot combustion on the catalyst.
参考文献
| [1] | Sun M;Wang L;Feng B N;Zhang Z G Lu G Z Guo Y .[J].Catalysis Today,2011,175:100. |
| [2] | Li Q;Meng M;Zhou Z Q;Li X G Zha Y Q .[J].Journal of Hazardous Materials,2009,161:366. |
| [3] | Kustov A L;Makkee M .[J].Applied Catalysis B:Environmental,2009,88:263. |
| [4] | Cousin R;Capelle S;Abi-Aad E;Courcot D;Aboukais A .Copper-vanadium-cerium oxide catalysts for carbon black oxidation[J].Applied Catalysis, B. Environmental: An International Journal Devoted to Catalytic Science and Its Applications,2007(26):247-253. |
| [5] | 韦岳长,刘坚,赵震,姜桂元,段爱军,何洪,王新平.Co_（0.2）/Ce_（1-x）Zr_xO_2催化剂的制备、表征及其催化碳烟燃烧反应性能[J].催化学报,2010(03):283-288. |
| [6] | 孙淑敏,楚文玲,杨惟慎.高热稳定性的铈铝复合氧化物用于柴油机尾气中碳烟的消除[J].催化学报,2009(07):685-689. |
| [7] | Shan W J;Ma N;Yang J L;Dong X W Liu C Wei L L .[J].Journal of Natural Gas Chemistry,2010,19:90. |
| [8] | 彭小圣,林赫,上官文峰,黄震.K和Cu部分取代对LaMnO3钙钛矿型催化剂同时去除Nox和碳烟的影响[J].催化学报,2006(09):767-771. |
| [9] | Setiabudi A;Chen J L;Mul G;Makkee M,Moulijn J A .[J].Appl Caral B,2004,51:9. |
| [10] | Issa M;Petit C;Brillard A;Brilhac J F .[J].Fuel,2008,87:740. |
| [11] | Atribak I;Such-Basá(n)ez I;Bueno-López A;Garc(i)a A .[J].Journal of Catalysis,2007,250:75. |
| [12] | Zaletova N V;Turakulova A O;Lunin V V .[J].Studies in Surface Science and Catalysis,2010,175:305. |
| [13] | Li, L.;Chen, F.;Lu, J.-Q.;Luo, M.-F. .Study of defect sites in ce1-xmxo2-δ (x = 0.2) solid solutions using raman spectroscopy[J].The journal of physical chemistry, A. Molecules, spectroscopy, kinetics, environment, & general theory,2011(27):7972-7977. |
| [14] | Bassou B;Guilhaume N;Lombaert K;Mirodatos C Bianchi D .[J].Energy and Fuels,2010,24:4781. |
| [15] | Milt V G;Querini C A;Miró E E;Ulla M A .[J].Journal of Catalysis,2003,220:424. |
| [16] | Milt V G;Peralta M A;Ulla M A;Miró E E .[J].Catalysis Communications,2007,8:765. |
| [17] | Weng D;Li J;Wu X D;Lin F .[J].Catalysis Communications,2008,9:1898. |
| [18] | Radovic L R;Walker J P L;Jenkins R G R G .[J].Journal of Catalysis,1983,82:382. |
| [19] | Shangguan W F;Teraoka Y;Kagawa S .[J].Applied Catalysis B:Environmental,1997,12:237. |
| [20] | Peralta M A;Zanuttini M S;Ulla M A;Querini C A .[J].Applied Catalysis,2011,399:161. |
| [21] | Castoldi L;Matarrese R;Lietti L;Forzatti P .[J].Applied Catalysis B:Environmental,2009,90:278. |
| [22] | Sui LN;Yu L Y .[J].Chemical Engineering Journal,2008,142:327. |
| [23] | Pruvost C;Lamonier J F;Courcot D;Abi-Aad E Aboukais A .[J].Studies in Surface Science and Catalysis,2000,130:2159. |
| [24] | Neeft JPA.;Makkee M.;Moulijn JA.;Hoornaert F. .THE EFFECTS OF HEAT AND MASS TRANSFER IN THERMOGRAVIMETRICAL ANALYSIS - A CASE STUDY TOWARDS THE CATALYTIC OXIDATION OF SOOT[J].Thermochimica Acta: An International Journal Concerned with the Broader Aspects of Thermochemistry and Its Applications to Chemical Problems,1996(2):261-278. |
| [25] | Krishna K;Bueno-Lopez A;Makkee M;Moulijn JA .Potential rare earth modified CeO2 catalysts for soot oxidation I. Characterisation and catalytic activity with O-2[J].Applied Catalysis, B. Environmental: An International Journal Devoted to Catalytic Science and Its Applications,2007(3/4):189-200. |
| [26] | Peralta M A;Zanuttini M S;Querini C A .[J].Applied Catalysis B:Environmental,2011,110:90. |
| [27] | Ahlstrom A F;Odenbrand C U I .[J].Applied Catalysis,1990,60:143. |
| [28] | Ito K;Kishikawa K;Watajima A;Ikeue K Machida M .[J].Catalysis Communications,2007,8:2176. |
| [29] | Zhang Y H;Zou X T .[J].Catalysis Communications,2007,8:760. |
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