Hydrogen-assisted SCR of NOx over alumina-supported silver and indium catalysts using C2-hydrocarbons and oxygenates
Artikel i vetenskaplig tidskrift, 2016

This work focuses on the selective catalytic reduction (SCR) of nitrogen oxides (NOx) with ethane, ethene, acetic acid, dimethyl ether (DME) and ethanol, respectively, over alumina-supported silver and indium catalysts. The impact of hydrogen and the nature of the reductant on the catalyst structure and SCR activity are studied. The ability to reduce NOx differs significantly among the studied reductants, but also between the two catalysts, of which Ag/Al2O3 is the overall most active catalyst. However, the In/Al2O3 catalyst exhibits high SCR activity with DME as reductant in contrast to the Ag/Al2O3 catalyst, which shows negligible activity. We attribute this difference to the higher number of acidic sites on the In/Al2O3 catalyst and the higher degree of DME combustion over Ag/Al2O3. Moreover, the number of sites that previously have been identified to promote hydrocarbon activation, i.e. silver cluster sites (Agnδ+) in Ag/Al2O3 catalysts and indium cluster sites (In3+) in In/Al2O3 catalysts, are shown to increase upon addition of small amounts of hydrogen in the feed. We suggest that the increased SCR activity over In/Al2O3 originates from an increased number of sites for activation of hydrocarbons, analogous to previous proposals for Ag-based catalysts, in combination with a direct effect on the reaction mechanism.

Indium–alumina

Lean NOx reduction

Silver-alumina

Hydrogen-assistance

HC-SCR

Författare

Linda Ström

Kompetenscentrum katalys (KCK)

Kemi och kemiteknik, Tillämpad kemi, Teknisk ytkemi

Per-Anders Carlsson

Kompetenscentrum katalys (KCK)

Kemi och kemiteknik, Tillämpad kemi, Teknisk ytkemi

Magnus Skoglundh

Kompetenscentrum katalys (KCK)

Kemi och kemiteknik, Tillämpad kemi, Teknisk ytkemi

Hanna Härelind

Kompetenscentrum katalys (KCK)

Kemi och kemiteknik, Tillämpad kemi, Teknisk ytkemi

Applied Catalysis B: Environmental

0926-3373 (ISSN) 1873-3883 (eISSN)

Vol. 181 403-412

Drivkrafter

Hållbar utveckling

Ämneskategorier

Materialteknik

Fysikalisk kemi

Kemiska processer

Kemiteknik

Fundament

Grundläggande vetenskaper

Styrkeområden

Materialvetenskap

DOI

10.1016/j.apcatb.2015.08.009