Impact of three-way catalyst formulation on reactivity in exhaust conditions relevant to propane-powered engines

Daekun  Kim, University of Tennessee

Daekun Kima, *, Todd J. Toopsb and Ke Nguyena

a University of Tennessee, Knoxville, TN 37996, United States

b Oak Ridge National Laboratories, Oak Ridge, TN 37831, United States

* – presenting author

 

The reactivity of five different formulations of a family of prototype three-way catalysts has been investigated in a bench-flow reactor using simulated exhaust gases with C3H8 as the only hydrocarbon component.  The formulations differ in the loading of Pd/Rh and the amount of the oxygen storage material. Results indicate that the formulation with a loading of Pd-only of 4.1 g/L and a medium amount of oxygen storage material offer the best performance with the lowest T50 and T90 for both CO and C3H8. On the other hand, T50 and T90 for NO are lowest in the bimetallic formulation without oxygen storage material; the loading of Pd and Rh is 6.4 g/L and 0.14 g/L, respectively. The formulation with a loading Pd of 1.51 g/L and a low amount of oxygen storage material exhibits the highest T50 and T90 for CO, NO, and C3H8. All prototype TWC samples were also investigated by using several catalytic probe reactions: water-gas-shift (WGS), steam reforming (SR) and oxygen storage capacity (OSC). Additionally, the TWC samples were characterized through N2 physisorption analysis to measure surface area, pore volume, and pore size distribution, before and after aging for 50h under US-DRIVE prescribed aging conditions.