Influence of platinum and rhodium composition on the NOx storage and sulphur tolerance of a barium based NOx storage catalyst
Journal article, 2003

In the present work the influence of the type of noble metals present in barium oxide based NOx storage catalysts was investigated, regarding the NOx storage performance, NO oxidation, NO reduction, sulphur deactivation and sulphur regenerability. Monolith samples with combinations of platinum and rhodium, were prepared, tested in a flow-reactor, and characterised by XPS measurements. The flow-reactor experiments simulated NOx storage and reduction cycles at 400 degrees C in synthetic gas mixtures with oxygen, propene and nitric oxide. For the sulphur deactivation and regenerability investigations 25 ppm (v/v) SO2 was added to the feed gas stream. From the experiments, it was concluded that a combination of platinum and rhodium is required to achieve good NOx storage and reduction performance. The NOx storage capacity was, however, found higher for catalysts containing only platinum compared to catalysts including rhodium. When exposed to SO2 the NOx storage capacity also seemed to deactivate faster for the samples containing rhodium than for samples with platinum as the sole noble metal. Additionally, it was observed that platinum gives high NO oxidation activity during the lean periods both with and without SO2 present in the gas feed. During the rich periods, rhodium showed high activity for NO reduction in sulphur free gas feed as well as in the presence of SO2. Finally, the results implied that to provide good sulphur regeneration ability of the NOx storage catalyst, a combination of platinum and rhodium is necessary.

NO reduction

NOx storage catalysts platinum

sulphur deactivation

NO oxidation

rhodium

Author

Annika Amberntsson

Competence Centre for Catalysis (KCK)

Chalmers, Applied Physics

Erik Fridell

Chalmers, Applied Physics, Chemical Physics

Competence Centre for Catalysis (KCK)

Magnus Skoglundh

Competence Centre for Catalysis (KCK)

Chalmers, Department of Materials and Surface Chemistry, Applied Surface Chemistry

Applied Catalysis B: Environmental

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

Vol. 46 3 429-439

Driving Forces

Sustainable development

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Transport

Energy

Materials Science

Subject Categories

Physical Chemistry

Chemical Engineering

Chemical Sciences

DOI

10.1016/S0926-3373(03)00269-8

More information

Created

10/7/2017