Design of Experiments Combined With High-Throughput Experimentation For The Optimization of DeNOx Catalysts
Engineering, Chemical Engineering, Catalysis and Reaction Engineering
Design of experiments in combination with high-throughput experimentation (HTE) is a powerful toolbox for the systematic study of vast parameter spaces encountered in the design and optimization of heterogeneous catalysts. We will present the general approach as applied to NOx storage and reduction (NSR) catalysts using response surface analysis. Empirical models were developed to predict the catalyst performance as a function of cycle time, lean fraction of cycle time, and catalyst composition. These models provide useful insight about the factors controlling the NOx storage and NOx conversion of NSR catalysts. Using these empirical models, new catalyst formulations that maximize NOx conversion and selectivity to N2 were found.
In addition, high-throughput experimentation allows for simultaneous synthesis and screening of large arrays of different materials which further accelerates the discovery and optimization process. We have also tested a variety of new materials for NSR applications, composed of different transition metals added to standard Pt/Ba-based NSR catalysts, and have discovered that a noble metal free 5Co/15Ba catalyst stores NOx as efficiently as a standard 1Pt/15Ba NSR catalyst. Using the response surface strategy we have verified that the addition of Co to NSR catalsyts improves the performance at higher lean fractions, allowing a substantial improvement in the fuel efficiency. These studies clearly establish the utility of HTE when combined with design of experiments for the efficient analysis of such vast multidimensional systems and for the discovery of new materials, which is the guiding factor for any major technological advances.
Digital Object Identifier (DOI)
Published in Studies in Surface Science and Catalysis, Volume 171, 2008, pages 325-359.
© Studies in Surface Science and Catalysis, 2008, Elsevier
Vijay, R., Lauterbach, A.J. (2008). Design of experiments combined with high-throughput experimentation for the optimization of DeNOx catalysts. Studies in Surface Science and Catalysis, 171, 325-359.