Abstract
A simple liquid water treatment applied to fresh and thermally aged Pt(2 wt%)–BaO(20 wt%)/Al2O3 lean NO x trap catalysts at room temperature induces morphological and structural changes in the barium species as followed by XRD and TEM analysis. During the water treatment, liquid water sufficient to fill the catalyst pore volume is brought into contact with the samples. It was found that irrespective of the original barium chemical state (highly dispersed BaO or crystalline BaAl2O4), exposing the sample to this liquid water treatment promotes the formation of BaCO3 crystallites (about 15–25 nm of its size) without changing the Pt particle size. Such transformations of the barium species are found to significantly promote NO x uptake from 250 to 450 °C. The increase in the NO x uptake for the water-treated samples can be attributed to an enhanced Pt–Ba interaction through the redistribution of barium species. These results provide useful information for the regeneration of aged lean NO x trap catalysts since water is plentiful in the exhaust of diesel or lean-burn engines.
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Takahashi N, Shinjoh H, Iijima T, Suzuki T, Yamazaki K, Yokota K, Suzuki H, Miyoshi N, Matsumoto S, Tanizawa T, Tanaka T, Tateishi S, Kasahara K (1996) Catal Today 27:63–69
Epling WS, Campbell LE, Yezerets A, Currier NW, Parks JE (2004) Catal Rev-Sci Eng 46:163–245
Engstrom P, Amberntsson A, Skoglundh M, Fridell E, Smedler G (1999) Appl Catal B-Environ 22:L241–L248
Amberntsson A, Skoglundh M, Ljungstrom S, Fridell E (2003) J Catal 217:253–263
Lietti L, Forzatti P, Nova I, Tronconi E (2001) J Catal 204:175–191
Jang BH, Yeon TH, Han HS, Park YK, Yie JE (2001) Catal Lett 77:21–28
Graham GW, Jen HW, Chun W, Sun HP, Pan XQ, McCabe RW (2004) Catal Lett 93:129–134
Fridell E, Persson H, Westerberg B, Olsson L, Skoglundh M (2000) Catal Lett 66:71–74
Li J, Theis JR, Chun W, Goralski C Jr, Kudla R, Ura J, Watkins W, Chattha M, Hurley R SAE paper (2001-01-2503)
Hodjati S, Bernhardt P, Petit C, Pitchon V, Kiennemann A (1998) Appl Catal B-Environ 19:209–219
Hodjati S, Bernhardt P, Petit C, Pitchon V, Kiennemann A (1998) Appl Catal B-Environ 19:221–232
Graham GW, Jen HW, Theis JR, McCabe RW (2004) Catal Lett 93:3–6
Kim DH, Chin YH, Kwak JH, Szanyi J, Peden CHF (2005) Catal Lett 105:259–268
Piacentini M, Maciejewski M, Baiker A (2005) Appl Catal B-Environ 60:265–275
Szanyi J, Kwak JH, Hanson J, Wang CM, Szailer T, Peden CHF (2005) J Phys Chem B 109:7339–7344
Datye AK, Xu Q, Kharas KC, McCarty JM (2006) Catal Today 111:59–67
Kim DH, Chin YH, Muntean GG, Yezeretz A, Currier NW, Epling WS, Chen HY, Hess H, Peden CHF (2006) Ind Eng Chem Res 45:8815–8821
Cant NW, Liu IOY, Patterson MJ (2006) J Catal 243:309–317
Kwak JH, Kim DH, Szailer T, Peden CHF, Szanyi J (2006) Catal Lett 111:119–126
Kim DH, Kwak JH, Szanyi J, Burton SD, Peden CHF (2007) Appl Catal B-Environ 72:233–239
Acknowledgment
Financial support was provided by the U.S. Department of Energy (DOE), Office of Energy Efficiency and Renewable Energy, Vehicle Technologies Program. The work was performed in the Environmental Molecular Sciences Laboratory (EMSL) at Pacific Northwest National Laboratory (PNNL). The EMSL is a national scientific user facility and supported by the U.S. DOE, Office of Biological and Environmental Research. PNNL is a multi-program national laboratory operated for the U.S. Department of Energy by Battelle Memorial Institute under Contract DE-AC06-76RLO 1830.
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Kim, D.H., Chin, YH., Kwak, J.H. et al. Promotional Effects of H2O Treatment on NO x Storage Over Fresh and Thermally Aged Pt–BaO/Al2O3 Lean NO x Trap Catalysts. Catal Lett 124, 39–45 (2008). https://doi.org/10.1007/s10562-008-9505-6
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DOI: https://doi.org/10.1007/s10562-008-9505-6