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Removal of Nitrogen Oxides Using Hydrocarbon Selective Catalytic Reduction Coupled with Plasma

플라즈마가 결합된 탄화수소 선택적 촉매환원 공정에서 질소산화물(NOx)의 저감

  • Received : 2015.12.29
  • Accepted : 2016.01.06
  • Published : 2016.02.10

Abstract

Low-temperature conversion of nitrogen oxides using plasma-assisted hydrocarbon selective catalytic reduction of (HC-SCR) was investigated. Plasma was created in the catalyst-packed bed so that it could directly interact with the catalyst. The effect of the reaction temperature, the shape of catalyst, the concentration of n-heptane as a reducing agent, the oxygen content, the water vapor content and the energy density on $NO_x$ removal was examined. $NO_x$ conversion efficiencies achieved with the plasma-catalytic hybrid process at a temperature of $250^{\circ}C$ and an specific energy input (SIE) of $42J\;L^{-1}$ were 83% and 69% for one-dimensional Ag catalyst ($Ag\;(nanowire)/{\gamma}-Al_2O_3$) and spherical Ag catalyst ($Ag\;(sphere)/{\gamma}-Al_2O_3$), respectively, whereas that obtained with the catalyst-alone was considerably lower (about 30%) even with $Ag\;(nanowire)/{\gamma}-Al_2O_3$ under the same condition. The enhanced catalytic activity towards $NO_x$ conversion in the presence of plasma can be explained by the formation of more reactive $NO_2$ species and partially oxidized hydrocarbon intermediates from the oxidation of NO and n-heptane under plasma discharge. Increasing the SIE tended to improve $NO_x$ conversion efficiency, and so did the increase in the n-heptane concentration; however, a further increase in the n-heptane concentration beyond $C_1/NO_x$ ratio of 5 did not improve the $NO_x$ conversion efficiency any more. The increase in the humidity affected negatively the $NO_x$ conversion efficiency, resulting in lowering the $NO_x$ conversion efficiency at the higher water vapor content, because water molecules competed with $NO_x$ species for the same active site. The $NO_x$ conversion efficiency increased with increasing the oxygen content from 3 to 15%, in particular at low SIE values, because the formation of $NO_2$ and partially oxidized hydrocarbon intermediates was facilitated.

Keywords

nitrogen oxides;hydrocarbon selective catalytic reduction;plasma

References

  1. J. Lee, J. Park, S. Kim, S. Yoo, and J. Kim, Kinetics of hydrogen rich ethanol as reductant for HC-SCR over $Al_2O_3$ supported Ag catalyst, Trans. Korean Hydrogen and New Energy Society, 21, 519-525 (2010).
  2. M. Kim and C. Lee, A study of hydrocarbon SCR (Selective Catalytic Reduction) on Ag/$\gamma$-$Al_2O_3$ catalyst, Analyt. Sci. Technol., 18, 139-146 (2005).
  3. S. S. Kim, D. H. Jang, and S. C. Hong, A study of the reaction characteristics on hydrocarbon selective catalytic reduction of $NO_x$ over various noble metal catalysts, Clean technol., 17, 225-230 (2011).
  4. Y. S. Mok, V. Ravi, H. C. Kang, and B. S. Rajanikanth, Abatement of nitrogen oxides in a catalytic reactor enhanced by nonthermal plasma discharge, IEEE Trans. Plasma Sci., 31, 157-165 (2003). https://doi.org/10.1109/TPS.2003.808876
  5. W. Sun, Q. Wang, S. Ding, S. Su, W. Jiang, and E. Zhu, Reaction mechanism of $NO_x$ removal from flue gas with pyrolusite slurry, Sep. Purif. Technol., 118, 576-582 (2013). https://doi.org/10.1016/j.seppur.2013.08.005
  6. J. O. Lee and Y. H. Song, Characteristics of low temperature De-$NO_x$ process with non-thermal plasma and $NH_3$ selective catalytic reduction (I), J. Korean Ind. Eng. Chem., 17, 409-413 (2006).
  7. D. Y. Yoon, J. H. Park, H. C. Kang, P. S. Kim, I. S. Nam, G. K. Yeo, J. K. Kil, and M. S. Cha, $DeNO_x$ performance of Ag/$Al_2O_3$ catalyst by n-dodecane: Effect of calcination temperature, Appl. Catal. B Environ., 101, 275-282 (2011). https://doi.org/10.1016/j.apcatb.2010.09.028
  8. D. Worch, W. Suprun, and R. Glaser, Supported transition metal- oxide catalysts for HC-SCR $DeNO_x$ with propene, Catal. Today, 176, 309-313 (2011). https://doi.org/10.1016/j.cattod.2010.12.008
  9. A. Gervasini, P. Carniti, and V. Ragaini, Studies of direct decomposition and reduction of nitrogen oxide with ethylene by supported noble metal catalysts, Appl. Catal. B Environ., 22, 201-213 (1999). https://doi.org/10.1016/S0926-3373(99)00053-3
  10. Y. Nie, J. Wang, K. Zhong, L. Wang, and Z. Guan, Synergy study for plasma-facilitated $C_2H_4$ selective catalytic reduction of $NO_x$ over Ag/$\gamma$-$Al_2O_3$ catalyst, IEEE Trans. Plasma Sci., 35, 663-669 (2007). https://doi.org/10.1109/TPS.2007.896764
  11. B. Meng, Z. Zhao, X. Wang, J. Liang, and J. Qiu, Selective catalytic reduction of nitrogen oxides by ammonia over $Co_3O_4$ nanocrystals with different shapes, Appl. Catal. B Environ., 129, 491-500 (2013). https://doi.org/10.1016/j.apcatb.2012.09.040
  12. T. -H. Ihm, J. -O. Jo, Y. J. Hyun, and Y. S. Mok, Size and shape effect of metal oxides on hydrocarbon selective catalytic reduction of nitrogen oxides, J. Korean Inst. Gas, 19, 20-28 (2015).
  13. H. Miessner, K. Francke, and R. Rudolph, Plasma-enhanced HC-SCR of $NO_x$ in the presence of excess oxygen, Appl. Catal. B Environ., 36, 53-62 (2002). https://doi.org/10.1016/S0926-3373(01)00280-6
  14. R. G. Tonkyn, S. E. Barlowa, and J. W. Hoard, Reduction of $NO_x$ in synthetic diesel exhaust via two-step plasma-catalysis treatment, Appl. Catal. B Environ., 40, 207-217 (2003). https://doi.org/10.1016/S0926-3373(02)00150-9
  15. K. G. Rappe, J. W. Hoard, C. L. Aardahl, P. W. Park, C. H. F. Peden, and D. N. Tran, Combination of low and high temperature catalytic materials to obtain broad temperature coverage for plasma- facilitated $NO_x$ reduction, Catal. Today, 89, 143-150 (2004). https://doi.org/10.1016/j.cattod.2003.11.020
  16. H. Y. Fan, C. Shi, X. S. Li, X. F. Yang, Y. Xu, and A. M. Zhu, Low-temperature $NO_x$ selective reduction by hydrocarbons on H-Mordenite catalysts in dielectric barrier discharge plasma, Plasma Chem. Plasma Proc., 29, 43-53 (2009). https://doi.org/10.1007/s11090-008-9160-0
  17. T. Furusawa, K. Seshan, J. A. Lercher, L. Lefferts, and K. Aika, Selective reduction of NO to N2 in the presence of oxygen over supported silver catalysts, Appl. Catal. B Environ., 37, 205-216 (2002). https://doi.org/10.1016/S0926-3373(01)00337-X
  18. H. He, Y. Li, X. Zhang, Y. Yu, and C. Zhang, Precipitable silver compound catalysts for the selective catalytic reduction of $NO_x$ by ethanol, Appl. Catal. A General, 375, 258-264 (2010). https://doi.org/10.1016/j.apcata.2010.01.002
  19. K. Shimizu, A. Satsuma1, and T. Hattori, Catalytic performance of Ag-$Al_2O_3$ catalyst for the selective catalytic reduction of NO by higher hydrocarbons, Appl. Catal. B Environ., 25, 239-247 (2000). https://doi.org/10.1016/S0926-3373(99)00135-6
  20. H. -E. Wagner, R. Brandenburg, K. V. Kozlov, A. Sonnenfeld, P. Michel, and J. F. Behnke, The barrier discharge: Basic properties and applications to surface treatment, Vacuum, 71, 417-436 (2003). https://doi.org/10.1016/S0042-207X(02)00765-0
  21. M. S. P. Sudhakaran, J. O. Jo, Q. H. Trinh, and Y. S. Mok, Characteristics of packed-bed plasma reactor with dielectric barrier discharge for treating ethylene, Appl. Chem. Eng., 26, 495-504 (2015). https://doi.org/10.14478/ace.2015.1066
  22. S. W. T. Sitshebo, HC-SCR of $NO_x$ Emissions Over Ag-$Al_2O_3$ Catalysts Using Diesel Fuel as a Reductant, PhD Dissertation, The University of Birmingham, Birmingham, United Kingdom (2010).
  23. R. Dorai and M. J. Kushner, Effect of multiple pulses on the plasma chemistry during the remediation of $NO_x$ using dielectric barrier discharges, J. Phys. D: Appl. Phys., 34, 574-583 (2001). https://doi.org/10.1088/0022-3727/34/4/319
  24. B. S. Rajanikanth and A. D. Srinivasan, Pulsed plasma promoted adsorption/catalysis for $NO_x$ removal from stationary diesel engine exhaust, IEEE Trans. Dielectr. Electr. Insul., 14, 302-311 (2007). https://doi.org/10.1109/TDEI.2007.344608
  25. Y. Pei, X. Chen, D. Xiong, S. Liao, and G. Wang, Removal and recovery of toxic silver ion using deep-sea bacterial generated biogenic manganese oxides, PLoS One, 8, e81627 (2013). https://doi.org/10.1371/journal.pone.0081627
  26. X. Tang, F. Feng, L. Ye, X. Zhang, Y. Huang, Z. Liu, and K. Yan, Removal of dilute VOCs in air by post-plasma catalysis over Ag-based composite oxide catalysts, Catal. Today, 211, 39-43 (2013). https://doi.org/10.1016/j.cattod.2013.04.026
  27. L. Jiang, R. Zhu, Y. Mao, J. Chen, and L. Zhang, Conversion characteristics and production evaluation of styrene/o-xylene mixtures removed by DBD pretreatment, Int. J. Environ. Res. Public Health, 12, 1334-1350 (2015). https://doi.org/10.3390/ijerph120201334
  28. W. G. Mallard, F. Westley, J. T. Herron, and R. Hampso, NIST Chemical Kinetics Database: Version 2Q98. Gaithersburg, MD, USA (1998).

Cited by

  1. Consideration of the Role of Plasma in a Plasma-Coupled Selective Catalytic Reduction of Nitrogen Oxides with a Hydrocarbon Reducing Agent vol.7, pp.11, 2017, https://doi.org/10.3390/catal7110325

Acknowledgement

Supported by : 한국연구재단