(570c) Effects of C12H26 and O2 on NO Uptake on Pd/SSZ-13: Experiments and Modeling
- Conference: AIChE Annual Meeting
- Year: 2021
- Proceeding: 2021 Annual Meeting
- Group: Catalysis and Reaction Engineering Division
- Time: Thursday, November 11, 2021 - 8:36am-8:54am
In our recent study we developed a one-dimensional two-phase transient monolith model containing a mechanistic-based microkinetic scheme to explain the NOxuptake and release over different PNA materials [1,2]. Model involves Z-[PdOH]+,Z-Pd2+Z- and Z-Pd+ as active sites. Here we will present experimental and modeling studies on the uptake of NO in the presence of C12H26 over a Pd/SSZ-13. When a co-feed containing C12H26 and NO is supplied to Pd/SSZ-13 catalyst, compared to NO-only feed, the NO uptake is unaffected but during the subsequent temperature ramp, the release of trapped NO is delayed to over 220oC from 175oC. The release delay is beneficial for PNA performance as the primary NOx aftertreatment technology Selective Catalytic Reduction (SCR) is not operated below 200oC. Oxidation of C12H26 leads to the generation of partial oxidation product CO. Carbon monoxide binds strongly to Pd sites with NO and can delay NO release. The developed model was extended to include the effects of C12H26 on NO uptake and release. Some of the modelling results are shown in Fig. 1. The model is validated at different uptake temperatures, temperature programmed desorption (TPD) ramp rates, and feed flow rates, affording its use to validate the experimental findings and to identify optimal operating strategies.