• About
  • Policies
  • What is open access
  • Library
  • Contact
Advanced search
      View Item 
      •   BUIR Home
      • Scholarly Publications
      • Faculty of Science
      • Department of Chemistry
      • View Item
      •   BUIR Home
      • Scholarly Publications
      • Faculty of Science
      • Department of Chemistry
      • View Item
      JavaScript is disabled for your browser. Some features of this site may not work without it.

      Chemical deactivation by phosphorous under lean hydrothermal conditions over Cu/BEA NH3-SCR catalysts

      Thumbnail
      View / Download
      3.2 Mb
      Author(s)
      Andonova, S.
      Vovk, E.
      Sjöblom, J.
      Ozensoy, E.
      Olsson, L.
      Date
      2014-04-05
      Source Title
      Applied Catalysis B: Environmental
      Print ISSN
      0926-3373
      Publisher
      Elsevier
      Volume
      147
      Pages
      251 - 263
      Language
      English
      Type
      Article
      Item Usage Stats
      114
      views
      115
      downloads
      Abstract
      To obtain a better understanding of the deactivation of SCR catalysts that may be encountered due to the presence of P-containing impurities in diesel exhausts, the effects induced by P over Cu/BEA NH3- SCR catalysts were studied as functions of the temperature of poisoning and P concentration in the feed. Cu/BEA catalysts with different Cu loadings (4 and 1.3 wt% Cu) were exposed to P by controlled evaporation of H3PO4 in the presence of 8% O2 and 5% H2O at 573 and 773K. The reaction studies were performed by NH3-storage/TPD, NH3/NO oxidation and standard NH3-SCR. In addition, a combination of several characterisation techniques (ICP–AES, BET surface area, pore size distribution, H2-TPR and XPS) was applied to provide useful information regarding the mechanism of P deactivation. Pore condensation of H3PO4 in combination with pore blocking was observed. However, the measured overall deactivation was found to occur mostly by chemical deactivation reducing the number of the active Cu species and hence deteriorating the redox properties of the Cu/BEA catalysts. The process of P accumulation on the surface preferentially occurs on the “over exchanged” Cu active sites with the formation of phosphate species. This is likely the reason for the more severe deactivation of the 4% Cu/BEA compared to 1.3% Cu/BEA. Further, the higher NOx reduction performance at 773K of the P-poisoned Cu/BEA catalysts was found to originate from the lower selectivity towards NH3 oxidation, which occurs predominately on the “over-exchanged” sites.
      Keywords
      Nh3 Scr
      Nox Reduction
      Cu/BEA catalysts
      P Poisoning
      Deactivation
      Permalink
      http://hdl.handle.net/11693/13492
      Published Version (Please cite this version)
      http://dx.doi.org/10.1016/j.apcatb.2013.08.041
      Collections
      • Department of Chemistry 640
      Show full item record

      Browse

      All of BUIRCommunities & CollectionsTitlesAuthorsAdvisorsBy Issue DateKeywordsTypeDepartmentsThis CollectionTitlesAuthorsAdvisorsBy Issue DateKeywordsTypeDepartments

      My Account

      LoginRegister

      Statistics

      View Usage StatisticsView Google Analytics Statistics

      Bilkent University

      If you have trouble accessing this page and need to request an alternate format, contact the site administrator. Phone: (312) 290 1771
      © Bilkent University - Library IT

      Contact Us | Send Feedback | Off-Campus Access | Admin | Privacy