Partial Regeneration of Model TWC After High-Temperature Aging on Engine Bench

Monometallic rhodium three-way catalyst supported on the ZrCeYLaO2 oxide system was prepared via impregnation method and subjected to high-temperature aging in an engine bench. The aged sample was additionally treated under model fuel-cut conditions, when the temperature was sharply reduced from 1000 degrees C to a room temperature. This kind of treatment was found to improve the overall catalytic activity and widen the operation window. The activated state of the catalyst was found to be stable and reproducible at repeated aging under hydrothermal conditions. Characterization of the initial and aged samples has shown that the effect of self-reactivation is connected with redistribution of agglomerated rhodium particles non-uniformly distributed on the particles of the ZrCeYLaO2 solid solution. In this case, the disadvantage of the preparation technique is appeared to have positive effect on the catalyst performance.