Reactions Over A Double Layer Tri-Metal Three-Way Catalyst

Edward Jobson; Ove Hjortsberg; S. Lennart Andersson; Ingemar Gottberg

doi:10.4271/960801

1996-02-01

Reactions Over A Double Layer Tri-Metal Three-Way Catalyst 960801

The reactions over a commercially available double layer tri-metal type (Pt, Pd, Rh) passenger car catalyst were analysed. A parameter study was performed in synthetic exhaust gases at: steady state conversion, periodic oscillations, and controlled transients. The influences of gas phase composition, temperature, adiabatic heat of reaction and lambda oscillations were investigated. The reactions of nitrogen oxides, propene and carbon monoxide were simultaneously analysed. Fast response emission analysers were used to record the dynamic properties of the catalysts.

The catalyst was found to have high conversion rates and high oxygen storage capacity at relatively low temperatures. The presence of sulphur dioxide was found to reduce the conversion of CO and NO_x substantially. An emission increase of 40-70 % was observed for steady state conditions and at oscillating conditions the increase was more than 100%. The experimental results were simulated in a dynamic model and a simplified reaction mechanism which explained the differences was proposed. The implications for catalyst diagnostics were discussed.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Digital $37.00 Print $37.00

Preview Document

We also recommend:

Standards

SAE Mobilus®

Publications

News

Events

Professional Development

A World in Motion (PreK-12)

Participate with SAE

SAE Membership

Donate

Reactions Over A Double Layer Tri-Metal Three-Way Catalyst 960801

SAE MOBILUS