|
|
氨催化还原NOx中TiO2负载过渡金属催化剂的催化行为
|
Abstract:
采用溶胶–凝胶法合成了TiO2催化剂载体，并通过浸渍法制备了一系列TiO2负载过渡金属脱硝催化剂。结合N2吸脱附、X射线衍射(XRD)和X射线光电子能谱(XPS)等手段，及催化活性评价研究了过渡金属/TiO2催化剂在氨选择催化还原NOx(NH3-SCR)中的催化行为。研究表明：过渡金属/TiO2催化剂活性为Mn/TiO2 > Fe/TiO2 > Cr/TiO2 > Co/TiO2。Mn/TiO2催化剂的脱硝活性最好，在250℃时最大脱硝效率达到93%。过渡金属/TiO2催化剂的脱硝活性与催化剂的比表面积和孔体积成正相关性。催化剂的活性组分是决定催化剂活性的主要因素，Mn/TiO2、Co/TiO2、Cr/TiO2和Fe/TiO2催化剂中活性组分分别为Mn4+、Co3O4、Cr3+和Fe3+。合适的氧活性物种比值(Olatt/Osurf = 4.7)和高活性的 Mn4+活性位使得Mn/TiO2催化剂具有高催化活性。
Support TiO2 was synthesized by sol-gel method, and a series of transition metal/TiO2 catalysts were prepared by impregnation method. Combination of N2 adsorption-desorption, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) and catalytic behavior of NO reduction with NH3 on transition metal/TiO2 catalysts were carried out by activity test. The results show that the activities of transition metal/TiO2 catalyst decrease in the order of Mn/TiO2 > Fe/TiO2 > Cr/TiO2 > Co/TiO2. Mn/TiO2 catalyst exhibits the highest activity among various catalysts, and the maximum de-NOx efficiency can reach 93% at 250？C. The deNOx activity of transition metal/TiO2 catalysts is positively correlated with the specific surface area and pore volume of the catalysts. The active component of the catalysts is the determining factor for the activity of the catalysts. The active sites of Mn/TiO2, Co/TiO2, Cr/TiO2 and Fe/TiO2 catalysts are Mn4+, Co3O4, Cr3+ and FeCr3+, respectively. A suitable ratio of oxygen active species (Olatt/Osurf = 4.7) and active sites of Mn4+ make the high activity of Mn/TiO2 catalyst.
| [1] | 蓝宁, 潘华, 陈郑辉, 吴谦, 骆迪迪. 铈基过渡金属复合氧化物上氨催化还原NOx的构效关系. 化学工程与技术, 2019, 9(2): 107-116. |
| [2] | Busca, G., Lietti, L., Ramis, G. and Berti, F. (1998) Chemical and Mechanistic Aspects of the Selective Catalytic Reduction of NOx by Ammonia over Oxide Catalysts: A Review. Applied Catalysis B: Environmental, 18, 1-36.
https://doi.org/10.1016/S0926-3373(98)00040-X |
| [3] | Hu, Y., Griffiths, K. and Norton, P.R. (2009) Surface Sci-ence Studies of Selective Catalytic Reduction of NO: Progress in the Last Ten Years. Surface Science, 603, 1740-1750. https://doi.org/10.1016/j.susc.2008.09.051 |
| [4] | Peng, Y., Li, J., Shi, W., Xu, J. and Hao, J. (2012) Design Strate-gies for Development of SCR Catalyst: Improvement of Alkali Poisoning Resistance and Novel Regeneration Method. Environmental Science & Technology, 46, 12623-12629. https://doi.org/10.1021/es302857a |
| [5] | Peng, Y., Li, J.H., Si, W.Z., Luo, J.M., Dai, Q.Z., Luo, X.B., Liu, X. and Hao, J.M. (2014) Insight Intodeactivation of Commercial SCR Catalyst by Arsenic: An Experiment and DFT Study. Environmental Science & Technology, 48, 13895-13900. https://doi.org/10.1021/es503486w |
| [6] | Jiang, Y., Gao, X., Zhang, Y., Wu, W., Song, H., Luo, Z. and Cen, K. (2014) Effects of PbCl2 on Selective Catalytic Reduction of NO with NH3 over Vanadia-Based Catalysts. Journal of Hazardous Materials, 274, 270-278.
https://doi.org/10.1016/j.jhazmat.2014.04.026 |
| [7] | Tian, W., Yang, H., Fan, X. and Zhang, X. (2011) Catalytic Reduction of NOx with NH3 over Different-Shaped MnO2 at Low Temperature. Journal of Hazardous Materials, 188, 105-109. https://doi.org/10.1016/j.jhazmat.2011.01.078 |
| [8] | Liu, Y., Xu, J., Li, H., Cai, S., Hu, H., Fang, C., Shi, L. and Zhang, D. (2015) Rational Design and in Situ Fabrication of MnO2@NiCo2O4 Nanowire Arrays on Ni Foam as High-Performance Monolith De-NOx Catalysts. Journal of Materials Chemistry A, 3, 11543-11553. https://doi.org/10.1039/C5TA01212K |
| [9] | Ma, Z., Yang, H., Li, Q., Zheng, J. and Zhang, X. (2012) Catalytic Re-duction of NO by NH3 over Fe-Cu-OX/CNTs-TiO2 Composites at Low Temperature. Applied Catalysis A: General, 427-428, 43-48.
https://doi.org/10.1016/j.apcata.2012.03.028 |
| [10] | Jiang, B., Liu, Y. and Wu, Z. (2009) Low-Temperature Selective Catalytic Reduction of NO on MnOx/TiO2 Prepared by Different Methods. Journal of Hazardous Materials, 162, 1249-1254. https://doi.org/10.1016/j.jhazmat.2008.06.013 |
| [11] | Fu, M.F., Li, C.T., Lu, P., Qu, L., Zhang, M.Y., Zhou, Y., Yu, M.G. and Fang, Y. (2014) A Review on Selective Catalytic Reduction of NOx by Supported Catalysts at 100 - 300？C—Catalysts, Mechanism, Kinetics. Catalysis Science &Technology, 4, 14-25. https://doi.org/10.1039/C3CY00414G |
| [12] | Jampaiah, D., Ippolito, S.J., Sabri, Y.M., Reddy, B.M. and Bhargava, S.K. (2015) Highly Efficient Nanosized Mn and Fe Codoped Ceria-Based Solid Solutions for Elemental Mercury Re-moval at Low Flue Gas Temperatures. Catalysis Science & Technology, 5, 2913-2924. https://doi.org/10.1039/C5CY00231A |
| [13] | Venkataswamy, P., Rao, K.N., Jampaiah, D. and Reddy, B.M. (2015) Nanostructured Manganese Doped Ceria Solid Solutions for CO Oxidation at Lower Temperatures. Applied Catalysis B: Environmental, 162, 122-132.
https://doi.org/10.1016/j.apcatb.2014.06.038 |
| [14] | Han, J., Meeprasert, J., Maitarad, P., Nammuangruk, S., Shi, L. and Zhang, D. (2016) Investigation of the Facet-Dependent Catalytic Performance of Fe2O3/CeO2 for the Selective Catalytic Reduction of NO with NH3. The Journal of Physical Chemistry C, 120, 1523-1533. https://doi.org/10.1021/acs.jpcc.5b09834 |
| [15] | 刘洪喜, 蒋业华, 詹兆麟, 汤宝寅. PIIID复合强化处理轴承钢表面TiN膜层的XPS表征. 光谱学与光谱分析, 2009, 29(9): 2585-2589. |
| [16] | Pan, H., Jian, Y. and Chen C. (2017) Sphere-Shaped Mn3O4 Catalyst with Remarkable Low-Temperature Activity for Methyl-Ethyl-Ketone Combustion. Environmental Science & Technology, 51, 6288-6297.
https://doi.org/10.1021/acs.est.7b00136 |
| [17] | 仲蕾. 铬基催化剂的制备及其催化氧化NO的性能研究[D]: [博士学位论文]. 南京: 南京理工大学, 2016. |
| [18] | Pan, H., Guo, Y.H. and Bi, H.T. (2015) NOX Adsorption and Re-duction with C3H6 over Fe/Zeolite Catalysts: Effect of Catalyst Support. Chemical Engineering Journal, 280, 66-73. https://doi.org/10.1016/j.cej.2015.05.093 |
| [19] | 任丽丽. 担载型分子筛催化剂上CH4选择还原NO反应的研究[D]: [博士学位论文]. 大连: 中国科学院大连化学物理研究所, 2003. |
