Lean NOx reduction over Ag/alumina catalysts via ethanol-SCR using ethanol/gasoline blends
Journal article, 2017

This study focuses on the activity for lean NOx reduction over sol-gel synthesized silver alumina (Ag/Al2O3) catalysts, with and without platinum doping, using ethanol (EtOH), EtOH/C3H6 and EtOH/gasoline blends as reducing agents. The effect of ethanol concentration, both by varying the hydrocarbon-to-NOx ratio and by alternating the gasoline concentration in the EtOH/gasoline mixture, is investigated. High activity for NOx reduction is demonstrated for powder catalysts for EtOH and EtOH/C3H6 as well as for monolith coated catalysts (EtOH and EtOH/gasoline). The results show that pure Ag/Al2O3 catalysts display higher NOx reduction and lower light-off temperature as compared to the platinum doped samples. The 4 wt.% Ag/Al2O3 catalyst displays 100% reduction in the range 340-425 degrees C, with up to 37% selectivity towards NH3. These results are also supported by DRIFTS (Diffuse reflection infrared Fourier transform spectroscopy) experiments. The high ammonia formation could, in combination with an NH3-SCR catalyst, be utilized to construct a NOx reduction system with lower fuel penalty cf. stand alone HC-SCR. In addition, it would result in an overall decrease in CO2 emissions.

HC-SCR

Silver-alumina

Lean NOx reduction

Ag/Al2O3

Platinum doping

Author

Fredrik Gunnarsson

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

Competence Centre for Catalysis (KCK)

J. A. Pihl

Oak Ridge National Laboratory

T. J. Toops

Oak Ridge National Laboratory

Magnus Skoglundh

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

Competence Centre for Catalysis (KCK)

Hanna Härelind

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

Competence Centre for Catalysis (KCK)

Applied Catalysis B: Environmental

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

Vol. 202 42-50

Driving Forces

Sustainable development

Areas of Advance

Transport

Energy

Materials Science

Subject Categories

Chemical Sciences

DOI

10.1016/j.apcatb.2016.09.009

More information

Created

10/8/2017