Impact of Thermal and Chemical Ageing of Fe-BEA SCR Catalyst on NOx Conversion Performance
Artikel i vetenskaplig tidskrift, 2016

Emissions of nitrogen oxides (NOx) from heavy-duty diesel engines are subject to more stringent environmental legislation. Selective catalytic reduction (SCR) over metal ion-exchanged zeolites is in this connection an efficient method to reduce NOx. Understanding durability of the SCR catalyst is crucial for correct design of the aftertreatment system. In the present paper, thermal and chemical ageing of Fe-BEA as NH3-SCR catalyst is studied. Experimental results of hydrothermal ageing, and chemical ageing due to phosphorous and potassium exposure are presented. The catalyst is characterized by flow reactor experiments, nitrogen physisorption, DRIFTS, XRD, and XPS. Based on the experimental results, a multisite kinetic model is developed to describe the activity of the fresh Fe-BEA catalyst. Furthermore, the model can predict deactivation of the catalyst well by decreasing the number of active sites, representing loss of active iron sites due to migration or chemical blockage of the sites. By performing a systematic study of different deactivation mechanisms, a deactivation expression for the active sites can be formulated.

Författare

Soran Shwan

Kompetenscentrum katalys (KCK)

Jonas Jansson

Kompetenscentrum katalys (KCK)

Magnus Skoglundh

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Teknisk ytkemi

Kompetenscentrum katalys (KCK)

SAE International Journal of Engines

1946-3936 (ISSN)

Vol. 9 2

Drivkrafter

Hållbar utveckling

Ämneskategorier

Materialteknik

Matematik

Kemiska processer

Kemiteknik

Styrkeområden

Transport

Energi

Materialvetenskap

Fundament

Grundläggande vetenskaper

DOI

10.4271/2016-01-0946

Mer information

Skapat

2017-10-08