The 4 PhD projects are related to the 4 scientific WPs as represented in the Figure, which also shows the institutions where the activities take place.
First principle DFT calculations of [Cu,S,O,H] motifs and kinetic modeling (WP1/WP2)
Objectives: To employ theoretical methods to investigate the structure and stability of [Cu,S,O,H] motifs as a function of catalyst state and conditions. To aid in the interpretation of experimental data by providing reliable structural, vibrational and electronic data. To calculate reaction mechanisms and to develop a microkinetic reaction scheme to include a quantitative description of SOx deactivation. To implement the kinetic reaction schemes into a catalyst simulation program, to parameterize the model based on lab data. To perform validation of the mechanistic models against experimental data from lab- and engine bench and to develop empirical models where the purely mechanistic approach fails. Apply the models to design more efficient ageing test cycles for model parameterization. Demonstrate application of the model towards the design of improved exhaust systems.
Expected Results: A validated model that describes the effect of thermal- and sulphur ageing on SCR performance. Project Title and Work Package(s) to which it is related:
Characterization and testing of SO2 poisoning effect on Cu-CHA zeolites (WP1/WP2)
Objectives: To identify the spectroscopic fingerprints of [Cu,S,O,H] motifs and identify their nature as a function of temperature, Cu oxidation state and regeneration cycles/procedures. To measure the catalytic activity as a function of SO2 poisoning conditions/regeneration cycles and to correlate the structure of [Cu,S,O,H] motifs to deactivation/catalyst performance.
Expected Results: To correlate the structure of [Cu,S,O,H] motifs to deactivation/catalyst performance.
Investigation of dealumination process in Cu-CHA catalysts (WP3/WP4)
Objectives: Understand what properties determine hydrothermal stability, focusing on deactivation phenomena not related to collapse of zeolite structure. Identify the fate of Cu and Al species upon hydrothermal aging. Investigate Al mobility
Expected Results: Description of the mechanisms for CHA dealumination and how it is affected by SOx.
Investigating the combined effect of SO2 poisoning and hydrothermal aging on Cu-CHA (WP3/WP4)
Objectives: Understand Difference in impact of SO2 on fresh and aged catalysts. Impact of SO2 on the (hydrothermal) aging process. Impact of aging on regeneration of SO2 deactivated catalysts. Implementation of mechanistic insights into the kinetic model created at Umicore.
Expected Results: A kinetic model that describes the characterization results of SCR catalysts that have seen different combinations of thermal- and Sulphur ageing.