2019, Volume 5, Issue 3
Engineering >> 2019, Volume 5, Issue 3 doi: 10.1016/j.eng.2019.02.005
Evaluation of H2 on the Evolution Mechanism of NOx Storage and Reduction over Pt–Ba–Ce/γ-Al2O3 Catalysts
School of Automotive and Traffic Engineering, Jiangsu University, Zhenjiang 212013, China
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Abstract
In this investigation, Pt–Ba–Ce/γ-Al2O3 catalysts were prepared by incipient wetness impregnation and experiments were performed to evaluate the influence of H2 on the evolution mechanism of nitrogen oxides (NOx) storage and reduction (NSR). The physical and chemical properties of the Pt–Ba–Ce/γ-Al2O3 catalysts were studied using a combination of characterization techniques, which showed that PtOx, CeO2, and BaCO3, whose peaks were observed in X-ray diffraction (XRD) spectra, dispersed well on the γ-Al2O3, as shown by transmission electron microscope (TEM), and that the difference between Ce3+ and Ce4+, as detected by X-ray photoelectron spectroscopy (XPS), facilitated the migration of active oxygen over the catalyst. In the process of a complete NSR experiment, the NOx storage capability was greatly
enhanced in the temperature range of 250–350 °C, and reached a maximum value of 315.3 μmol·g−1cat at 350 °C, which was ascribed to the increase in NO2 yield. In a lean and rich cycling experiment, the results showed that NOx storage efficiency and conversion were increased when the time of H2 exposure (i.e., 30 s, 45 s, and 60 s) was extended. The maximum NOx conversion of the catalyst reached 83.5% when the duration of the lean and rich phases was 240 and 60 s, respectively. The results revealed that increasing the content of H2 by an appropriate amount was favorable to the NSR mechanism due to increased decomposition of nitrate or nitrite, and the refreshing of trapping sites for the next cycle of NSR.
Keywords
Pt–Ba–Ce/γ-Al2O3 catalysts ; Physicochemical properties ; NOx storage and reduction ; NOx emission ; H2 reductant
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References
[ 1 ] Fridell E, Skoglundh M, Westerberg B, Johansson S, Smedler G. NOx storage in barium-containing catalysts. J Catal 1999;183(2):196–209. link1
[ 2 ] Rico-Pérez V, García-Cortés JM, Bueno-López A. NOx reduction to N2 with commercial fuel in a real diesel engine exhaust using a dual bed of Pt/beta zeolite and RhOx/ceria monolith catalysts. Chem Eng Sci 2013;104(50):557–64. link1
[ 3 ] Park S, Choi B, Kim H, Kim JH. Hydrogen production from dimethyl ether over Cu/c-Al2O3 catalyst with zeolites and its effects in the lean NOx trap performance. Int J Hydrogen Energy 2012;37(6):4762–73. link1
[ 4 ] Dai H. Environmental catalysis: a solution for the removal of atmospheric pollutants. Sci Bull 2015;60(19):1708–10. link1
[ 5 ] Wu W, Wang X, Jin S, Wang R. LaCoO3 perovskite in Pt/LaCoO3/K/Al2O3 for the improvement of NOx storage and reduction performances. RSC Adv 2016;6 (78):74046–52. link1
[ 6 ] Harold MP. NOx storage and reduction in lean burn vehicle emission control: a catalytic engineer’s playground. Curr Opin Chem Eng 2012;1(3):303–11. link1
[ 7 ] He X, Meng M, He J, Zou Z, Li X, Li Z, et al. A potential substitution of noble metal Pt by perovskite LaCoO3 in ZrTiO4 supported lean-burn NOx trap catalysts. Catal Commun 2010;12(3):165–8. link1
[ 8 ] Rui Y, Zhang Y, Liu D, Meng M, Jiang Z, Zhang S, et al. A series of ceria supported lean-burn NOx trap catalysts LaCoO3/K2CO3/CeO2 using perovskite as active component. Chem Eng J 2015;260:357–67. link1
[ 9 ] Perng CCY, Easterling VG, Harold MP. Fast lean-rich cycling for enhanced NOx conversion on storage and reduction catalysts. Catal Today 2014;231 (8):125–34. link1
[10] Kabin KS, Muncrief RL, Harold MP, Li Y. Dynamics of storage and reaction in a monolith reactor: lean NOx reduction. Chem Eng Sci 2004;59(22):5319–27. link1
[11] Mei X, Wang J, Yang R, Yan Q, Wang Q. Synthesis of Pt doped Mg-Al layered double oxide/graphene oxide hybrid as novel NOx storage-reduction catalyst. RSC Adv 2015;5(95):78061–70. link1
[12] Atribak I, Bueno-López A, García-García A. Combined removal of diesel soot particulates and NOx over CeO2–ZrO2 mixed oxides. J Catal 2008;259 (1):123–32. link1
[13] Casapu M, Grunwaldt JD, Maciejewski M, Baiker A, Eckhoff S, Gobel U, et al. The fate of platinum in Pt/Ba/CeO2 and Pt/Ba/Al2O3 catalysts during thermal aging. J Catal 2007;251(1):28–38. link1
[14] Roy S, Baiker A. NOx storage-reduction catalysis: from mechanism and materials properties to storage-reduction performance. Chem Rev 2009;109 (9):4054–91. link1
[15] Caglar B, Uner D. NO oxidation and NOx storage over Ce–Zr mixed oxide supported catalysts. Catal Commun 2011;12(6):450–3. link1
[16] Le Phuc N, Courtois X, Can F, Royer S, Marecot P, Duprez D. NOx removal efficiency and ammonia selectivity during the NOx storage-reduction process over Pt/BaO(Fe, Mn, Ce)/Al2O3 model catalysts. Part II: influence of Ce and Mn– Ce addition. Appl Catal B 2011;102(3):362–71. link1
[17] Lin S, Yang L, Yang X, Zhou R. Redox properties and metal-support interaction of Pd/Ce0.67Zr0.33O2–Al2O3 catalyst for CO, HC and NOx elimination. Appl Surf Sci 2014;305:642–9. link1
[18] AL-Harbi M, Epling WS. Effects of different regeneration timing protocols on the performance of a model NOx storage/reduction catalyst. Catal Today 2010;151(3–4):347–53. link1
[19] Masdrag L, Courtois X, Can F, Duprez D. Effect of reducing agent (C3H6, CO, H2) on the NOx conversion and selectivity during representative lean/rich cycles over monometallic platinum based NSR catalysts. Influence of the support formulation. Appl Catal B 2014;146(5):12–23. link1
[20] Abdulhamid H, Fridell E, Skoglundh M. Influence of the type of reducing agent (H2, CO, C3H6, and C3H8) on the reduction of stored NOx in a Pt/BaO/Al2O3 model catalyst. Top Catal 2004;30(1–4):161–8. link1
[21] Ansari F, Sobhani A, Salavati-Niasari M. Simple sol–gel synthesis and characterization of new CoTiO3/CoFe2O4 nanocomposite by using liquid glucose, maltose and starch as fuel, capping and reducing agents. J Colloid Interface Sci 2018;514:723–32. link1
[22] Amiri O, Mir N, Ansari F, Salavati-Niasari M. Design and fabrication of a high performance inorganic tandem solar cell with 11.5% conversion efficiency. Electrochim Acta 2017;252:315–21. link1
[23] Mahdiani M, Sobhani A, Ansari F, Salavati-Niasari M. Lead hexaferrite nanostructures: green amino acid sol–gel auto-combustion synthesis, characterization and considering magnetic property. J Mater Sci Mater Electron 2017;28(23):17627–34. link1
[24] Mahdiani M, Soofivand F, Ansari F, Salavati-Niasari M. Grafting of CuFe12O19 nanoparticles on CNT and graphene: eco-friendly synthesis, characterization and photocatalytic activity. J Clean Prod 2018;176:1185–97. link1
[25] Shi C, Ji Y, Graham UM, Jacobs G, Crocker M, Zhang Z, et al. NOx storage and reduction properties of model ceria-based lean NOx trap catalysts. Appl Catal B 2012;119–120:183–96. link1
[26] Shinjoh H, Hatanaka M, Nagai Y, Tanabe T, Takahashi N, Yoshida T, et al. Suppression of noble metal sintering based on the support anchoring effect and its application in automotive three-way catalysis. Top Catal 2009;52:1967. link1
[27] Shi C, Zhang ZS, Crocker M, Xu L, Wang C, Au C, et al. Non-thermal plasmaassisted NOx storage and reduction on a LaMn0.9Fe0.1O3 perovskite catalyst. Catal Today 2013;211(4):96–103. link1
[28] Peuckert M. XPS investigation of surface oxidation layers on a platinum electrode in alkaline solution. Electrochim Acta 1984;29(10): 1315–20. link1
[29] Zhang ZS, Chen BB, Wang XK, Xu L, Au C, Shi C, et al. NOx storage and reduction properties of model manganese-based lean NOx trap catalysts. Appl Catal B 2015;165:232–44. link1
[30] Jing L, Xu Z, Sun X, Shang J, Cai W. The surface properties and photocatalytic activities of ZnO ultrafine particles. Appl Surf Sci 2001;180(3–4): 308–14. link1
[31] Kang M, Park ED, Kim JM, Yie JE. Manganese oxide catalysts for NOx reduction with NH3 at low temperatures. Appl Catal A 2007;327(2):261–9. link1
[32] Persson K, Ersson A, Jansson K, Fierro J, Jaras S. Influence of molar ratio on Pd–Pt catalysts for methane combustion. J Catal 2006;243(1):14–24. link1
[33] Infantes-Molina A, Righini L, Castoldi L, Loricera CV, Fierro JLG, Sin A, et al. Characterization and reactivity of Ce-promoted PtBa lean NOx trap catalysts. Catal Today 2012;197(1):178–89. link1
[34] Lietti L, Forzatti P, Nova I, Tronconi E. NOx storage reduction over Pt–Ba/c-Al2O3 catalyst. J Catal 2001;204(1):175–91. link1
[35] Symalla MO, Drochner A, Vogel H, Büchel R, Pratsinis SE, Baiker A. Structure and NOx storage behaviour of flame-made BaCO3 and Pt/BaCO3 nanoparticles. Appl Catal B Environ 2009;89(1–2):41–8. link1
[36] Broqvist P, Panas I, Grönbeck H. Toward a realistic description of NOx storage in BaO: the aspect of BaCO3. J Phys Chem B 2005;109(19):9613–21. link1
[37] Castoldi L, Righini L, Matarrese R, Lietti L, Forzatti P. Mechanistic aspects of the release and the reduction of NOx stored on Pt–Ba/Al2O3. J Catal 2015;328:270–9. link1
[38] Mudiyanselage K, Weaver JF, Szanyi J. Catalytic decomposition of Ba(NO3)2 on Pt(111). J Phys Chem C 2011;115(13):5903–9. link1
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