IR-spectroscopy based multi-site kinetic modeling for NH 3 -SCR on Fe-BEA

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Renewable energies Eco-friendly production Innovative transport Eco-efficient processes Sustainable resources IR-spectroscopy based multi-site kinetic modeling for NH 3 -SCR on Fe-BEA Stavros SKARLIS

1 Renewable energies Eco-friendly production Innovative transport Eco-efficient processes Sustainable resources IR-spectroscopy based multi-site kinetic modeling for NH 3 -SCR on Fe-BEA Stavros SKARLIS CLEERS Workshop 213 Technical advisors team André NICOLLE (Supervisor, IFPEN) David BERTHOUT (Supervisor, IFPEN) Christophe DUJARDIN (Academic Supervisor, Univ. Lille 1) Pascal GRANGER (Thesis Director, Univ. Lille 1) UCCS Université Lille 1

2 Outline Fe-zeolite based Urea-SCR catalysts A multi-site kinetic modeling approach IR spectroscopy based multi-site kinetic modeling Fe-BEA synthesis and characterization NH 3 adsorption: IR spectroscopic measurements Modeling and simulation Conclusions and perspectives 2

3 Outline Fe-zeolite based Urea-SCR catalysts A multi-site kinetic modeling approach IR spectroscopy based multi-site kinetic modeling Fe-BEA synthesis and characterization NH 3 adsorption: IR spectroscopic measurements Modeling and simulation Conclusions and perspectives 3

and Lee 25-1-3881, SAE Technical Paper 15 2 25 3 35 4 45 5 Temperature [ C] Alumina (Al 2 O 3 ) Silicate (SiO 2 ) natural or synthetic

4 Fe-zeolite based Urea-SCR catalysts (1/2) Fe-zeolites as SCR catalysts 1 - High deno x efficiency over a broad range of temperatures: 2 55 C - Resistance to hydrothermal ageing NOx conversion [%] V2O5/TiO2 based catalyst Fe-exchanged zeolite Cu-exchanged zeolite 2 Schmieg and Lee , SAE Technical Paper Temperature [ C] Alumina (Al 2 O 3 ) Silicate (SiO 2 ) natural or synthetic materials 4 SiO 4 4- AlO 4 5- bza.org - H proton: acidic properties - Exchanging the proton with transition metals (Fe, Cu,...): redox properties

5 Fe-zeolite based Urea-SCR catalysts (2/2) NH 3 -SCR chemistry over Fe-zeolites Temperature ( C) Standard-SCR O 2 (ads) NO (g) > 25 C >18 C NH 3 (ads) NH 4 NO 2 (ads) N 2 (g) HNO 2 (ads) H 2 O(g) NO 2 (ads) NO (g) H 2 O (ads) O 2 (ads) NO 3 (ads) HNO 3 (ads) NH 3 (ads) NH 4 NO 3 (ads) NO (g) N 2 (g) H 2 O(g) NO 2 -SCR > 25 C N 2 (g) H 2 O (g) > 2 C N O 2 (g) H 2 O (g) Low Temp. Poisoning Non acidic sites Brønsted acidic sites Metallic sites Lewis acidic sites Fast-SCR NH 4 NO 3 (ads) <15 C Fe(OH) Fe 2 O(OH) 2 Monomeric species Dimeric (oligomeric) species NO 2 /NO x (%) Iwasaki et al. A. Cat. A Gen. (21), 39, Brandenberger et al. J. Catal. (29) 268, Grossale et al. Catal. Lett. (29) 13, Granger et al. Chem. Rev. (211) 111, Brandenberger et al. A. Cat. A Gen. (21) 373,

6 Outline Fe-zeolite based Urea-SCR catalysts A multi-site kinetic modeling approach IR spectroscopy based multi-site kinetic modeling Fe-BEA synthesis and characterization NH 3 adsorption: IR spectroscopic measurements Modeling and simulation Conclusions and perspectives 6

7 A multi-site kinetic modeling approach (1/2) Multi-site kinetic modeling of NH 3 adsorption and desorption on Fe-ZSM5 NH3 concentration [ppm] Non acidic sites Fe sites Weak acidic sites Si/Al=13.5 Strong acidic sites H-ZSM5 1.1% Fe-ZSM5 2% Fe-ZSM5 5% Fe-ZSM5 C 8 3 Preadsorption of 1% NH 3 à 3 C 1 C/min 6 min Temperature [ C] Exp. results by Brandenberger et al. (J. Catal., (29), 268, ) Symbols: Experimental results Lines: Simulation results SKARLIS et al. J. Phys. Chem. C (212) 116,

A multi-site kinetic modeling approach (2/2) NH 3 concentration [ppm] 35 3 25 2 15 1 5 5 1 15 2 25 3 35 4 45 5 55 Temperature [ C] Experimental Results Multi-site approach 1% NH 3 preads. 2%wt.

8 A multi-site kinetic modeling approach (2/2) NH 3 concentration [ppm] Temperature [ C] Experimental Results Multi-site approach 1% NH 3 preads. 2%wt. Fe-ZSM5 Si/Al=13.5 SKARLIS et al. TRA Europe 212 Cummulative ammount of desorbed NH 3 [mol] Experimental Results Multi-site approach Temperature [ C] Multi-site kinetic modeling approach evaluation Phenomenological approach Precision Experimental results required for model development Kinetics calibration complexity 8

9 Outline Fe-zeolite based Urea-SCR catalysts A multi-site kinetic modeling approach IR spectroscopy based multi-site kinetic modeling Fe-BEA synthesis and characterization NH 3 adsorption: IR spectroscopic measurements Modeling and simulation Conclusions and perspectives 9

10 Fe-BEA synthesis and characterization (1/2) Fe-BEA synthesis Parent zeolite: H-BEA (Si/Al=11.8) [IFP EN] Synthesis method: Wet ion exchange Fe precursor: Fe(NO 3 ) 3 aqueous solution Protocol: G. Delahay et al. (A. Cat. B: Environ., 55, ) ICP-AES results Element Composition Molar amount Fe Al Si (wt.%) (mol/kg cat. )

11 Fe-BEA synthesis and characterization (2/2).1 A 3745 cm -1 Ex-situ IR In vacuum Surface sites characterization 3782 cm -1 : Framework Al (FAl) Intensity 3782 cm cm cm -1 H + exchange 3745 cm -1 : Terminal silanol 3665 cm -1 : Extra-framework Al (EfAl) 366 cm -1 : OH + Brønsted acidic sites H-BETA BEA Wavenumber [cm -1 ] 35 Fe-BETA 33 Fe 2 O 3 XRD Fe-BEA Fe 3+ isolated species Fe clusters UV-vis Fe-BEA 11 F(R ) Fe 3+ isolated species Fe 2 O 3 particles Wavelength [nm] 2θ [ ] Intensity [a.u.] Intensity [a.u.] θ [ ]

12 Outline Fe-zeolite based Urea-SCR catalysts A multi-site kinetic modeling approach IR spectroscopy based multi-site kinetic modeling Fe-BEA synthesis and characterization NH 3 adsorption: IR spectroscopic measurements Modeling and simulation Conclusions and perspectives 12

13 NH 3 adsorption: IR spectroscopic measurements (1/4) Experimental set-up Gas phase analysis Solid phase analysis 1 mg H- & Fe-BEA Crushed in pellet P = P atm. 13

14 Intensity NH 3 adsorption: IR spectroscopic measurements (2/4) Measurements on H-BEA.1 A N 2 H cm -1 NH 3 -Al 163 cm -1 a: t=1 min f: t=75 min f a 15 cm -1 NH cm -1 Experimental conditions 5 ppm NH 3 balance He T ads. = 3 C Δt ads. = 75 min NH 4 + bidentate NH 4 + tridentate Diff. spectrum End of adsorption 16 Wavenumber [cm -1 ] 15 Adspecies characterization 15 cm -1 : weakly H-bonded NH cm -1 : NH 3 on Al (Lewis acidic sites) 1467 cm -1 : NH 4 + on Brønsted acidic sites 17 cm -1 : N 2 H 7+ - Multi-layer adsorption 14 Intensity A NH 4 + monodentate 15 cm cm Wavenumber [cm -1 ] 1432 cm H O Si Al N 135

15 NH 3 adsorption: IR spectroscopic measurements (3/4) Measurements on Fe-BEA H-BETA.1 A 146 cm -1.1 A Fe-BETA 146 cm cm -1 a: t=1 min f: t=8 min 162 cm cm cm -1 a: t=1 min f: t=8 min 162 cm cm -1 Intensity 3782 cm cm -1 e a Intensity 3782 cm -1 H + exchange by Fe 361 cm -1 e a Diff. spectrum End of adsorption Diff. spectrum End of adsorption Wavenumber [cm -1 ] Experimental conditions 5 ppm NH 3 balance He T ads. = 15 C Δt ads. = 8 min Wavenumber [cm -1 ] Formation of Lewis type Fe sites

16 NH 3 adsorption: IR spectroscopic measurements (4/4) NH 3 adspecies thermal stability 4 NH 3 -TPD + IR spectroscopy Temperature [C] H-bonded N2H7N 2 H 7 NH3-Al 3 NH3 4 IAS NH3 3 -Fe NH3 HAS 4 NH3 3 bidentate tridentate 16

17 Outline Fe-zeolite based Urea-SCR catalysts A multi-site kinetic modeling approach IR spectroscopy based multi-site kinetic modeling Fe-BEA synthesis and characterization NH 3 adsorption: IR spectroscopic measurements Modeling and simulation Conclusions and perspectives 17

18 Modeling and simulation (1/5) Kinetic model S1a site for weak adsorption and physisorption NH (g) 3 + S1a NH 3 S1a S1b weak Brønsted and Lewis sites NH 3 multi-layer formation on S1a and S1b sites S2 intermediate Brønsted acidic sites S3 strong Brønsted acidic sites S4 monomeric and/or binuclear Fe NH (g) 2NH 3 + S1b NH 3 S1b NH (g) NH (g) NH (g) 3 + NH (g) 3 Sj NH3 NH3 NH3 Sj 3 + S2 NH 3 S2 3 + S3 NH 3 S3 3 + S4 NH 3 S4 R R j _ NH j _ NH 3 3 _ ads _ des Reaction rate expressions E j _ NH ads 3 _ = Aj NH ads C NH R T _ exp 1 3 _ 3 s = A j _ NH 3 _ des exp E j _ NH 3 _ des R T ( 1 a ϑ ) s j ( ϑ ) j j ϑ j 18

The IFP-Exhaust Library LMS.Imagine.Lab AMESim D SCR Catalyst modeling IFP Exhaust Library Equivalent channel approach D solid energy balance dts ρs Cps Vs = hs Sgeom.

External/Internal species diffusion through Thiele modulus approach k ( c c ) m, i s g, i s, i η i & ωi = V wash tanh( φ) ηi = φ tanh( φ) φ 1 + Bim 19 Modeling the exhaust line

19 The IFP-Exhaust Library LMS.Imagine.Lab AMESim D SCR Catalyst modeling IFP Exhaust Library Equivalent channel approach D solid energy balance dts ρs Cps Vs = hs Sgeom. ( T g Ts ) + S dt S = Q + Q + Q conv. reac. rad. External/Internal species diffusion through Thiele modulus approach k ( c c ) m, i s g, i s, i η i & ωi = V wash tanh( φ) ηi = φ tanh( φ) φ 1 + Bim 19 Modeling the exhaust line using components m C Equivalent channel: gas balances Momentum/Energy/Species dqconv. dvmixt. = mi hi + Pg i dt dt dcg, i = ( c& g, i _ in c& g, i _ out) +φ dt Catalytic reactor modeling based on the bond graph theory dtg dt g v P P in out = d ρ A w g open 32 m& g µ Lmono. film m g i ω& dxi ui dt = v i R i i dm dt g C dt v

20 Modeling and simulation (2/5) Reproduction of experimental set-up Ambient Temperature Oven (heat flux component) D - Single Wafer Reactor Flow Meter Single Wafer Reactor & m g _ in D inj. ( 1.7mm) L cl. (1.7 mm) pellet & m g _ out Mixer (valve) D pel. (16mm ) FTIR Gas Analyzer (dead volume included) outlet gas port Assembled reactor Mixture Preparation thermocouple position open section area covered by IR lenses groove for pellet placing Assumptions Number of reactors computed based on the Péclet number Oven modeled through imposed external heat conduction Dead volume included inlet gas port Single wafer reactor geometry 2

21 Modeling and simulation (3/5) Kinetic parameters calibration Type of site A ads [m 3 /s kg zeolite ] E ads [kj/mol] A des [mol/s kg zeolite ] E des [kj/mol] α [-] S1a (sites for physisorption and weak adsprption) S1b (weak acidic sites) Multi-layer formation on S1a, S1b sites S2 (intermediate Brønsted sites) S3 (strong Brønsted sites) S4 (metallic sites) Entropy change Non activated process Immobile molecules NH 3 storage capacity estimation over each site based on Fe-BEA structural properties: Si/Al and Fe/Al Data obtained from catalyst characterization: Ex-situ IR NH 3 -TPD profiles obtained over the H- and Fe-BEA studied samples Data from thermo-gravimetric measurements Homogeneous acidity strength SKARLIS et al. J. Phys. Chem. C ,

22 SKARLIS et al. J. Phys. Chem. C , Modeling and simulation (4/5) Adsorption phase TPD phase 6 Tads.=3 C (exp.) Tads.=15 C (exp.) 12 Tads.=3 C (exp.) Tads.=15 C (exp.) NH3 concentration [ppm] Tads.=35 C (exp.) NH3inlet NH3 concentration [ppm] 8 4 Tads.=35 C (exp.) time [min] Symbols: Experimental results Temperature [ C] Lines: Simulation results NH 3 concentration [ppm] 6 ppm NH 3 He balance T ads 1% He 1% He 1 C/min 41 C NH 3 concentration [ppm] 6 ppm NH 3 He balance T ads 1% He 1% He 1 C/min 41 C time [min] time [min]

23 SKARLIS et al. J. Phys. Chem. C , Modeling and simulation (5/5) Effect of He purge duration Effect of T-ramping 14 5 min He purge (exp.) 28 dt/dt=1 C/min (exp.) dt/dt=15 C/min (exp.) NH3 concentration [ppm] h He purge (exp.) 5 h He purge (exp.) NH3 concentration [ppm] dt/dt=2 C/min (exp.) Temperature [ C] Symbols: Experimental results Temperature [ C] Lines: Simulation results 23 NH 3 concentration [ppm] 6 ppm NH 3 He balance 3 C 1% He 8 t purge 1% He 1 C/min 41 C time [min] NH 3 concentration [ppm] 6 ppm NH 3 He balance 3 C 1% He % He dt/dt ( C/min) 41 C time [min]

24 Outline Fe-zeolite based Urea-SCR catalysts A multi-site kinetic modeling approach IR spectroscopy based multi-site kinetic modeling Fe-BEA synthesis and characterization NH 3 adsorption: IR spectroscopic measurements Modeling and simulation Conclusions and perspectives 24

Conclusions and perspectives Multi-site kinetic model for NH 3 adsorption and desorption over Fe-BEA Chemisorption on intermediate and strong Brønsted sites Model development based on IR

25 Conclusions and perspectives Multi-site kinetic model for NH 3 adsorption and desorption over Fe-BEA Chemisorption on intermediate and strong Brønsted sites Model development based on IR spectroscopic measurements Kinetics calibration according to theoretical and experimental studies H des [kj/mol] 15 1 Chemisorption on Fe sites Chemisorption on weak Brønsted and Lewis sites Physisorption Adsorption temperature [ C] H O Si Al Fe N Further extension of the multi-site kinetic model to include additional reactions is underway 25

26 Absorbance Model extension to NO x adsorption Operando IR spectroscopic measurements over the 1.75% Fe-BEA NO cm -1 NO cm cm -1 Absorbance 1592 cm -1 Absorbance 1517 cm -1 NO 2 23 cm cm cm cm cm cm Multi-site kinetic modeling NO + S NO 2 O S 2O S 3NO + 2 S + O S 2NO3 S NO(g) NO + O S NO 2 S S 1 Experimental Results Simulation Results Temperature [ C] NO x outlet concentration [ppm] NO 2 -TPD over a commercial Fe-zeolite Exp. results by Grossale et al. Cat. Today 136 (28) 18 27

27 Thank you for your kind attention Sincere acknowledgements to Mr. J.C. Morin as well as Drs. S. Carré, N. Rankovic and N. Bats for their contribution to the presented work The presented work was performed under supervision of: David Berthout a, André Nicolle a, Christophe Dujardin b, Pascal Granger b a IFP Energies Nouvelles, France b Unité de Catalyse et de Chimie du Solide - Université de Lille 1, France 27

28 Renewable energies Eco-friendly production Innovative transport Eco-efficient processes Sustainable resources

Development and Validation of a multi-site kinetic model for NH 3 -SCR over Cu-SSZ-13. Rohil Daya Isuzu Technical Center of America

Development and Validation of a multi-site kinetic model for NH 3 -SCR over Cu-SSZ-13 Rohil Daya Isuzu Technical Center of America Introduction, Objective and Purpose Cu-CHA small pore SCR catalysts utilized