Volume 8, Issue 5, September 2020, Page: 112-124
Simulating the Effects of Poisoning on the Rate of the Oxidation of Ammonia over a V2O5/TiO2 Monolithic Diesel SCR Catalyst Using a Multichannel Model
Clas Ulf Ingemar Odenbrand, Department of Chemical Engineering, LTH Faculty of Engineering, Lund University, Lund, Sweden
Received: Sep. 2, 2020;       Accepted: Sep. 19, 2020;       Published: Oct. 30, 2020
DOI: 10.11648/j.ajche.20200805.12      View  139      Downloads  81
The background to this study is the need to find out if some reactions of O2 oxidation of ammonia oxidation are important in the Selective Catalytic Reduction (SCR) of NO by NH3. The objective of the study was to shed light on the influence of poisoning on these reactions over a diesel SCR catalyst by compounds in the exhaust gases. The method used was to experimentally determine the amounts of products formed at several temperatures and compared them to simulated values. About 700 ppm NH3 was oxidized by 2% O2 in helium yielding N2, N2O, and NO at increasing temperatures. Comparisons are given for a 4.56% vanadia on titania fresh catalyst and the ones used for 890 and 2299 h. The kinetics was simulated using a multichannel model of the monolithic catalyst. The experimental values of the products were nicely fitted by the kinetic model where all three ammonia oxidation reaction rates were of the first order in the concentration of ammonia. The fit was somewhat better for the non-isothermal case than the isothermal one. The deactivation reduces the activation energies for the formation of all products. Effects of flow and concentration maldistribution are shown to be present but are quite small. The temperature increase is 1.30 K for the most active catalyst at the highest temperature (733 K). The use of the multichannel model shows that quite considerable deviations in inlet ammonia concentrations are obtained over the catalyst cross section. This means that the catalyst is not used to its full potential.
Oxidation of Ammonia, Poisoning and Kinetics, Monolithic Multichannel Model, Vanadia SCR Catalyst
To cite this article
Clas Ulf Ingemar Odenbrand, Simulating the Effects of Poisoning on the Rate of the Oxidation of Ammonia over a V2O5/TiO2 Monolithic Diesel SCR Catalyst Using a Multichannel Model, American Journal of Chemical Engineering. Vol. 8, No. 5, 2020, pp. 112-124. doi: 10.11648/j.ajche.20200805.12
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A. Konstandopoulos, D. Zarvalis, L. Chasapidis, L. Deloglou, N. Vlachos, A. Kotbra, and G. Anderson, Investigation of SCR Catalysts for Marine Diesel Applications, SAE International Journal of Engines, Vol. 10 (4), pp. 1653-1666, 2017.
C. U. I. Odenbrand, Penetration of Poisons Along the Monolith Length of a V2O5/TiO2 Diesel SCR Catalyst and Its Effect on Activity, Catalysis Letters, Vol. 149 (12), pp. 3476-3490, 2019.
C. U. I. Odenbrand, The kinetics of the oxidation of ammonia on a V2O5/TiO2 catalyst deactivated in an engine rig. Part I. Determination of kinetic parameters by simulation, Environmental Research & Technology, Vol. 2 (4), pp. 211-221, 2019.
U. S. Ozkan, Y. Cai, M. W. Kuthekar, and L. Zhang, Role of Ammonia Oxidation in Selective Catalytic Reduction of Nitric Oxide over Vanadia Catalysts, Journal of Catalysis, Vol. 142, pp. 182-197, 1993.
U. S. Ozkan, Y. Cai, and M. W. Kuthekar, Investigation of the Mechanism of Ammonia Oxidation and Oxygen Exchange over Vanadia Catalysts Using N-15 and O-18 Tracer Studies, Journal of Catalysis, Vol. 149, pp. 375-389, 1994.
B. L. Duffy, H. E. Curry-Hyde, N. W. Cant, and P. F. Nelson, Isotopic Labelling Studies of the Effects of Temperature, Water and Vanadia Loading on the Selective Catalytic Reduction of NO with NH3 over Vanadia-Titania Catalysts, Journal of Physical Chemistry, Vol. 98, pp. 7153-7161, 1994.
A. M. Efstathiou, and K. Fliatoura, Selective catalytic reduction of nitric oxide with ammonia over V2O5/TiO2 catalyst; A steady-state and transient kinetic study, Applied Catalysis B: Environmental., Vol. 6, pp. 35-59, 1995.
S. Djerad, M. Crocoll, S. Kureti, L. Tifouti, and W. Weisweler, Effect of oxygen concentration on the NOx reduction with ammonia over V2O5-WO3/TiO2 catalyst, Catalysis Today, Vol. 113, pp. 208-214, 2006.
N. Usberti, M. Jablonska, M. Di Blasi, P. Forzatti, P. Lietti, Design of a "high-efficiency" NH3-SCR reactor for stationary applications. A kinetic study of NH3 oxidation and NH3-SCR over V-based catalysts, Appl. Catal. B: Environ. Vol. 179, pp. 185-195, 2015.
H. J. Chae, T. C. Cho, H. Choi, I.-S. Nam, H. S. Yang, S. L. Song, Direct Use of Kinetic Parameters for Modeling and Simulation of a Selective Catalytic Reduction Process, Ind. Eng. Chem. Res., Vol. 39, pp. 1159-1170.
I. Nova, L. dall' Acqua, L. Lietti, E. Giamello, P. Forzatti, Study of thermal deactivation of a de-NOx commercial catalyst, Appl. Catal. B: Environ. Vol. 35 (1), pp. 31-42, 2001.
C.-T. Chen, W.-L. Tan, Mathematical modeling, optimal design and control of an SCR reactor for NOx removal, J. of the Taiwan Institute of Chemical Engineers, Vol. 43, pp. 409-419, 2012.
B. K. Yun, M. Y. Kim, Modeling the selective catalytic reduction of NOx by ammonia over a Vanadia-based catalyst from heavy duty diesel exhaust gases, Appl. Thermal Engineering, Vol. 50, pp. 152-158. 2013.
J. Om, P. Ji, W. Wu, 3D Numerical Simulation of Gas Flow and Selective Catalytic Reduction (SCR) of NO in the Honeycomb Reactor, Asia-Pacific Energy Equipment Engineering Research Conference (AP3ER 2015) pp. 56-65, 2015. Atlantis Press.
F. Millo, M. Rafigh, D. Fino, P. Micelli, Application of a global kinetic model on an SCR coated on Filter (SCR-F) catalyst for automotive applications, Fuel Vol. 198, pp. 183-192, 2017.
A. Åberg, A. Widd, J. Abildskov, J. Kjöbsted Huusom, Parameter estimation and analysis of an automotive heavy-duty SCR catalyst model, Chem. Eng. Sci., Vol. 161, pp. 167-177, 2017.
Shin SB, Skau KI, Menon M, Maroor S, A modelling approach to kinetic study and novel monolith channel design for selective catalytic reduction (SCR) applications, Chem. Eng. Res. Des., Vol. 142, pp. 412-428, 2019.
C. U. I. Odenbrand, High Temperature and High Concentration SCR of NO with NH3 for the Oxyfuel Combustion Process: Fitting of Kinetics to Data from a Laboratory Reactor Experiment, Topics in Catalysis, Vol. 60, pp, 1317-1332, 2017.
C. U. I. Odenbrand, CaSO4 deactivated V2O5- WO3/TiO2 SCR catalyst for a diesel power plant. Characterisation and simulation of the kinetics of the SCR reactions, Applied Catalysis B: Environmental, Vol. 234, pp. 365-377, 2018.
J. G. M. Brandin, and C. U. I. Odenbrand, Poisoning of SCR Catalysts used in Municipal Waste Incineration Applications, Topics in Catalysis, Vol. 60, pp. 1306-1316, 2017.
J. G. M. Brandin, and C. U. I. Odenbrand, Deactivation and Characterisation of SCR Catalysts Used in Municipal Waste Incineration Applications, Catalysis Letters, Vol. 148 (1), pp. 312-327, 2018.
S. Salehi, M. A. Moghaddam, and N. Sahebjamee, Modeling Transport Phenomena in Selective Catalytic Reductant Catalytic Converter with NH3 as reductant for NO Degradation, International Journal of Engineering, Vol. 29 (9), pp. 1183-1190, 2016.
G. Schaub, D. Unruh, J. Wang, and T. Turek, Kinetic analysis of selective catalytic NOx reduction (SCR) in a catalytic filter, Chemical Engineering and Processing, Vol. 42, pp. 365-371, 2003.
J. Due-Hansen, A. L. Kustov, C. Hviid Christensen, and R. Fehrmann, Impact of support and potassium-poisoning on the V2O5-WO3/ZrO2 catalyst performance in the ammonia oxidation, Catalysis Communications, Vol. 10, pp. 803-806, 2009.
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