Community Research and Development Information Service - CORDIS


Automobile 3-way catalytic converters are usually based on a ceramic honeycomb material (cordierite) on to which is placed a washcoat consisting of an alumina/ceria layer containing finely dispersed particles of a noble metal catalyst.

The high temperature reactions of SO(2) or H(2)S on catalyst supports or washcoats have been almost entirely neglected in the literature. This lack of data and understanding has been addressed in a series of experiments in which two commercial grades of cordierite support with a normal washcoat were exposed for periods up to 500 hours at temperatures between 600 C and 1000 C in simple environments containing sulphur.

After exposure, the materials were examined for chemical and morphological changes by optical and scanning electron microscopy with EDX analysis. In addition to cracking and spallation, chemical attack of the washcoat by SO(2)/SO(3) with the formation of water soluble cerium sulphate was found to be significant. Finally, a comparison is made with material cut from a used automobile catalytic converter monolith. th.

Additional information

Authors: FORDHAM R J, JRC Petten (NL);COSTA OLIVEIRA F A, JRC Petten (NL);NORTON J F, JRC Petten (NL);QUADAKKERS W J, Forschungszentrum Jülich GmbH, Institute for Materials in Energy Systems (DE)
Bibliographic Reference: Paper presented: Microscopy of Oxidation, Cambridge (GB), September 16-18, 1996
Availability: Available from (1) as Paper EN 40792 ORA
Record Number: 199711119 / Last updated on: 1997-09-16
Original language: en
Available languages: en