Investigation on the Role of Pd, Pt, Rh in Methane Abatement for Heavy Duty Applications

Methane abatement remains a challenge in aftertreatment systems of natural gas engines, currently under discussion combination with synthetic methane. In this study, Pt/Rh and Pd/Rh-based three-way catalysts are investigated various transient conditions because transients between O2 excess (lean) O2-poor (rich) can significantly enhance methane abatement. At mid to high temperatures, transitions from rich lean feed yield higher rates direct oxidation the catalyst, compared Pd/Rh catalyst. Both able trigger steam reforming (SR) after feed. The SR reaction leads increased H2 NH3 formation. However, deactivates much faster low temperature, catalyst is more active for SR. Results an additional Pd-only confirm that Rh essential NOx conversion N2 selectivity. distinct characteristics Pt, Pd demonstrate benefits obtained three platinum group metals. potential Pt/Pd/Rh proved be significant throughout complete engine map. Under optimized lean/rich oscillatory conditions, yields than 95% almost all while maintaining efficient other pollutants.