Unprecedented propane–SCR-NOx activity over template-free synthesized Al-rich Co-BEA* zeolite

0450878 - ÚFCH JH 2016 RIV US eng J - Článek v odborném periodiku
Sazama, Petr - Mokrzycki, Lukasz - Wichterlová, Blanka - Vondrová, Alena - Pilař, Radim - Dědeček, Jiří - Sklenák, Štěpán - Tabor, Edyta
Unprecedented propane–SCR-NOx activity over template-free synthesized Al-rich Co-BEA* zeolite.
Journal of Catalysis. Roč. 332, DEC 2015 (2015), s. 201-211. ISSN 0021-9517. E-ISSN 1090-2694
Grant CEP: GA TA ČR(CZ) TH01021259; GA ČR GA15-13876S
Institucionální podpora: RVO:61388955
Klíčová slova: beta zeolite * Al-rich BEA* * OSDA-free synthesis
Kód oboru RIV: CF - Fyzikální chemie a teoretická chemie
Impakt faktor: 7.354, rok: 2015

An Al-rich Co-BEA* zeolite (Si/Al 4.2, Co/Al 0.5) was prepared by organotemplate-free hydrothermal synthesis and [Co(II)(H2O)6]2+ ion exchange. The structure of the Co species and their activity in C3H8–SCR-NOx were compared to that of Si-rich Co-BEA* (Si/Al 11.3). The high population of AlSiAl sequences in Al-rich BEA* with AlO4− facing different channels, contrary to their absence in Si-rich BEA*, results in dehydrated Co-BEA* in easily reducible counter-ion [Co(III)O]+ species attached to one AlO4−. The high concentration and density of these Co-oxo species in Al-rich Co-BEA* facilitates extra-ordinarily high SCR-NOx rate even under water vapor up to 10 vol.%, twelve-times outperforming Si-rich Co-BEA*. The five-to-six times increased TOF and easier reducibility suggest a synergetic redox effect of water-resistant Co-oxo species. The Al-rich Co-BEA* provides the highest reaction rate at conditions of wet NOx streams, exceeding that previously reported for metal ion/oxo zeolite catalysts, with a high selectivity to molecular nitrogen and efficient utilization of propane.
Trvalý link: http://hdl.handle.net/11104/0252227