This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Hydrogen Effect on the DeNO X Efficiency Enhancement of Fresh and Aged Ag/Al 2 O 3 HC-SCR in a Diesel Engine Exhaust
Technical Paper
2011-01-1278
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
HC-SCR is more convenient when compared to urea-SCR, since for
HC-SCR, diesel fuel can be used as the reductant which is already
available onboard the vehicle. However, the DeNOX
efficiency for HC-SCR is lower than that of urea-SCR in both low
and high temperature windows. In an attempt to improve the
DeNOX efficiency of HC-SCR, the effect of hydrogen were
evaluated for the fresh and aged catalyst over 2 wt.% Ag/Al₂O₃
using a Euro-4 diesel engine.
In this engine bench test, diesel fuel as the reductant was
injected directly into the exhaust gas stream and the hydrogen was
supplied from a hydrogen bomb. The engine was operated at 2,500 rpm
and BMEP 4 bar. The engine-out NOX was around 180
ppm-200 ppm. H₂/NOX and HC₁/NOX ratios were
5, 10, 20, and 3, 6, 9, respectively. The HC-SCR inlet exhaust gas
temperatures were around 215°C, 245°C, and 275°C. The catalyst
volumes used in this test were 2.5L and 5L for both fresh and aged
catalysts.
The DeNOX efficiency of the 5L fresh catalyst was in
the range of 0-25% without hydrogen, but it increased to 14-79%
when the hydrogen was added to the feed stream. The final
efficiency was a function of the hydrocarbon and hydrogen
concentrations in the exhaust gas mixtures and the HC-SCR inlet
temperatures. The NOX conversion efficiency of the 5L
aged catalyst, which had been aged thermally at 750°C for 25 hrs in
an electrical furnace, was in the range of 6-75% with hydrogen and
2-22% without hydrogen. In case of the 2.5L catalyst, the
DeNOX efficiency was in the range of 8-35% for the fresh
catalyst and 3-9% for the aged catalyst with hydrogen. In the
absence of hydrogen, the NOX conversion rate was in the
range of 3-8% and 3-5% for the fresh and aged catalyst,
respectively.
Recommended Content
Authors
Citation
Kim, K., Chun, K., Song, S., Han, H. et al., "Hydrogen Effect on the DeNOX Efficiency Enhancement of Fresh and Aged Ag/Al2O3 HC-SCR in a Diesel Engine Exhaust," SAE Technical Paper 2011-01-1278, 2011, https://doi.org/10.4271/2011-01-1278.Also In
References
- Eränan, K. Lindfors, L.-E. Niemi, A. Elfving, P. et al. “Influence of Hydrocarbons on the Selective Catalytic Reduction of NOx over Ag/Al2O3 - Laboratory and Engine Tests,” SAE Technical Paper 2000-01-2813 2000 10.4271/2000-01-2813
- Shimizu, K. Satusma, A. Hattori, T. “Catalytic performance of Ag-Al 2 O 3 catalyst for the selective catalytic reduction of NO by higher hydrocarbons” Appl. Catal. B 25 239 247 2000
- Satokawa, S. Shibata, J. Shimizu, K. Satsuma, A. Hattori, T. “Promotion Effect of H2 on the Low Temperature Activity of the Selective Reduction of NO by Light Hydrocarbons over Ag/Al 2 O 3 ” Appl. Catal. B 42 179 186 2003
- Houel, V. Millington, P. Rajaram, R. Tsolakis, A. “Fuel effects on the activity of silver hydrocarbon-SCR catalysts” Appl. Catal. B 73 203 207 2007
- Schmieg, S.J. Sloane, T.M. Blint, R.J. “Catalysts for Lean-Burn Engine Exhaust Aftertreatment Using Hydrocarbon Selective Catalytic Reduction,” SAE Int. J. Fuels Lubr. 2 2 323 336 2009 10.4271/2009-01-2819
- Lee, J. Song, S. Chun, K.M. “Study on fuel-reforming-assisted hydrocarbon selective reduction over silver/alumina catalyst” Ind. Eng. Chem. Res. 49 8 3553 3560 2010
- Burch, R. Breen, J.P. Hill, C.J. Krutzsch, B. Konrad, B. Jobson, E. Cider, L. Eranen, K. Klingstedt, F. Lindfords, L.-E. “Exceptional activity for NO X reduction at low temperature using combination of hydrogen and higher hydrocarbons on Ag/Al 2 O 3 catalyst” Topics in Catalysis 30/31 19 25 2004
- Arve, K. Backman, H. Klingstedt, F. Eranen, K. Murzin, D.Y. “Hydrogen as a remedy for the detrimental effect of aromatic and cyclic compounds on the HC-SCR over Ag/alumina” Appl. Catal. B 70 5 72 2007
- Houel, V. Millington, P. Rajaram, R. Tsolakis, A. “Promoting functions of H 2 in diesel-SCR over silver catalysts” Appl. Catal. B 77 23 24 2007
- Schmieg, S.J. Blint, R.J. Deng, L. “Control Strategy for the Removal of NO x from Diesel Engine Exhaust using Hydrocarbon Selective Catalytic Reduction,” SAE Int. J. Fuels Lubr. 1 1 1540 1552 2008 10.4271/2008-01-2486
- Eranen, K. Kligstedt, F. Arve, K. Lindfors, L. Murzin, D.Y. “On the mechanism of the selective catalytic reduction of NO with higher hydrocarbons over a silver/alumina catalyst” J. Catal. 227 328 343 2004
- Wichterlova, B. Sazama, P. Breen, J.P. Burch, R. Hill, C.J. Capek, L. Sobalik, Z. “An in situ UV-vis and FTIR spectroscopy study of the effect of H 2 and CO during the selective catalytic reduction of nitrogen oxides over a silver alumina catalyst” J. Catal. 235 195 200 2005
- Backman, H. Arve, K. Klingstedt, F. Murzin, D.Y. “Kinetic considerations of H 2 assisted hydrocarbon selective catalytic reduction of NO over Ag/Al 2 O 3 I. Kinetic modeling” Appl. Catal. A 303 96 102 2006
- Backman, H. Arve, K. Klingstedt, F. Murzin, D.Y. “Kinetic considerations of H 2 assisted hydrocarbon selective catalytic reduction of NO over Ag/Al 2 O 3 II. Kinetic modeling” Appl. Catal. A 304 86 92 2006
- Satokawa, S. Shibata, J. Shimizu, K. Satsuma, A. Hattori, T. Kojima, T. “Promotion effect of hydrogen on lean NOX reduction by hydrocarbons over Ag/Al2O3 catalyst” Chemical Engineering Science 62 5335 5337 2007
- Houel, V. James, D. Millington, P. Pollington, S. Poulston, S. Rajaram, R. Torbati, R. “A comparison of the activity and deactivation of Ag/Al 2 O 3 and Cu/ZSM-5 for HC-SCR under simulated diesel exhaust emission conditions” J. Catal. 230 150 157 2005
- Breen, J.P. Burch, R. Hardacre, C. Hill, C.J. Krutzsch, B. Bandl-Konard, B. Jobson, E. Cider, L. Blakeman, P.G. Peace, L.J. Twigg, M.V. Preis, M. Gottschling, M. “An Investigation of the thermal stability and sulphur tolerance of Ag/r-Al 2 O 3 catalysts for the SCR of NO X with hydrocarbons and hydrogen” Appl. Catal. B 70 36 44 2007
- Schmieg, S.J. “Aspects of HC-SCR Catalyst Durability for Lean-Burn Engine Exhaust Aftertreatment,” SAE Int. J. Fuels Lubr. 3 2 691 709 2010 10.4271/2010-01-2160